Table 1 . summary Distribution of all variables
| label | levels | all |
|---|---|---|
| Age | Mean (SD) | 47.2 (10.1) |
| Sex | FEMALE | 62 (62.0) |
| MALE | 38 (38.0) | |
| Smoking | Non-Smoker | 80 (80.0) |
| Smoker | 20 (20.0) | |
| SBP | Mean (SD) | 145.0 (15.2) |
| DBP | Mean (SD) | 88.4 (9.3) |
| FBS | Mean (SD) | 148.8 (26.6) |
| PPBS | Mean (SD) | 176.0 (33.5) |
| HBA1C | Mean (SD) | 7.4 (0.7) |
| ABPI | Mean (SD) | 1.0 (0.1) |
| ASCVD | Mean (SD) | 7.8 (2.5) |
| CRP | Mean (SD) | 6.8 (3.6) |
| HDL | Mean (SD) | 32.4 (6.8) |
| LDL | Mean (SD) | 152.0 (29.7) |
| TG | Mean (SD) | 202.0 (40.9) |
| Total_Cholesterol | Mean (SD) | 224.8 (31.9) |
| Urea | Mean (SD) | 40.0 (11.3) |
| Creatinine | Mean (SD) | 1.2 (0.2) |
| PAD | NOT PAD | 67 (67.0) |
| PAD | 33 (33.0) |
Table 2 . summary Distribution of all variables ,Groupwise(Case vs Control )
| label | levels | cases | control | p |
|---|---|---|---|---|
| Age | Mean (SD) | 47.0 (10.4) | 47.8 (9.0) | 0.566 |
| Sex | FEMALE | 50 (62.5) | 12 (60.0) | 0.837 |
| MALE | 30 (37.5) | 8 (40.0) | ||
| Smoking | Non-Smoker | 65 (81.2) | 15 (75.0) | 0.532 |
| Smoker | 15 (18.8) | 5 (25.0) | ||
| SBP | Mean (SD) | 150.1 (11.6) | 124.6 (10.0) | <0.001 |
| DBP | Mean (SD) | 92.0 (6.0) | 74.0 (5.0) | <0.001 |
| FBS | Mean (SD) | 160.0 (15.0) | 104.0 (9.9) | <0.001 |
| PPBS | Mean (SD) | 190.0 (20.0) | 119.9 (5.9) | <0.001 |
| HBA1C | Mean (SD) | 7.7 (0.3) | 6.0 (0.2) | <0.001 |
| abpi | Mean (SD) | 0.9 (0.1) | 1.1 (0.1) | <0.001 |
| ascvd | Mean (SD) | 9.0 (1.0) | 3.2 (0.2) | <0.001 |
| crp | Mean (SD) | 8.0 (3.0) | 2.1 (0.7) | <0.001 |
| HDL | Mean (SD) | 30.0 (5.0) | 42.0 (4.1) | <0.001 |
| LDL | Mean (SD) | 165.0 (15.0) | 100.0 (9.9) | <0.001 |
| TG | Mean (SD) | 220.0 (20.1) | 129.9 (15.0) | <0.001 |
| Total_Cholesterol | Mean (SD) | 239.0 (15.2) | 168.1 (10.8) | <0.001 |
| Urea | Mean (SD) | 45.1 (5.0) | 19.9 (5.0) | <0.001 |
| Creatinine | Mean (SD) | 1.3 (0.1) | 0.9 (0.1) | <0.001 |
| PAD | NOT PAD | 48 (60.0) | 19 (95.0) | 0.003 |
| PAD | 32 (40.0) | 1 (5.0) |
Table 3 . summary Distribution of all variables ,Groupwise(PAD vs Non PAD )
| label | levels | NOT PAD | PAD | p |
|---|---|---|---|---|
| Age | Mean (SD) | 47.7 (10.1) | 46.1 (10.2) | 0.220 |
| Sex | FEMALE | 41 (61.2) | 21 (63.6) | 0.813 |
| MALE | 26 (38.8) | 12 (36.4) | ||
| Smoking | Non-Smoker | 56 (83.6) | 24 (72.7) | 0.202 |
| Smoker | 11 (16.4) | 9 (27.3) | ||
| Group | cases | 48 (71.6) | 32 (97.0) | 0.003 |
| control | 19 (28.4) | 1 (3.0) | ||
| SBP | Mean (SD) | 144.2 (16.4) | 146.4 (12.5) | 0.805 |
| DBP | Mean (SD) | 87.4 (10.3) | 90.4 (6.4) | 0.285 |
| FBS | Mean (SD) | 144.6 (29.1) | 157.4 (18.0) | 0.081 |
| PPBS | Mean (SD) | 170.1 (36.1) | 187.9 (23.6) | 0.056 |
| HBA1C | Mean (SD) | 7.2 (0.8) | 7.6 (0.4) | 0.140 |
| ABPI | Mean (SD) | 1.0 (0.1) | 0.8 (0.1) | <0.001 |
| ASCVD | Mean (SD) | 7.5 (2.8) | 8.5 (1.4) | 0.548 |
| CRP | Mean (SD) | 6.8 (3.6) | 6.8 (3.5) | 0.702 |
| HDL | Mean (SD) | 33.4 (7.4) | 30.4 (5.1) | 0.055 |
| LDL | Mean (SD) | 147.0 (32.9) | 162.1 (18.2) | 0.113 |
| TG | Mean (SD) | 195.7 (45.8) | 214.8 (24.4) | 0.196 |
| Total_Cholesterol | Mean (SD) | 219.6 (35.8) | 235.4 (18.6) | 0.172 |
| Urea | Mean (SD) | 37.5 (12.0) | 45.2 (7.2) | 0.002 |
| Creatinine | Mean (SD) | 1.2 (0.2) | 1.3 (0.1) | 0.076 |
Distribution of Demographic Variables in Our Population
Fig.1 Plot of Age distribution across Groups
The Dodged bar chart above represents individual counts representing frequency of age_grp categories 40-50,30-40,50-60,60-70,20-30 and 80-90 in categories cases and control . Subgroup 40-50 has highest percentage 26/80 ( 32.5 % ) in Diabetic group . Subgroup 50-60 has highest percentage 11/20 ( 55 % ) in Control group . To formally check for association between groups we performed pearson chi-square test .
we found a Non-significant association between age_grp and Group(Cases and Control) . The chi-square statistic was 7.38 . The degree of freedom was 5 and P value was 0.19 .Contingency and Proportion table are shown below
Table 4
| Group | age_grp | n | value | 95 % Confidence Interval |
|---|---|---|---|---|
| cases | 20-30 | 2 | 2/80 ( 2.5 %) | 0.52% - 7.78% |
| cases | 30-40 | 21 | 21/80 ( 26.25 %) | 17.57% - 36.61% |
| cases | 40-50 | 26 | 26/80 ( 32.5 %) | 23% - 43.24% |
| cases | 50-60 | 22 | 22/80 ( 27.5 %) | 18.64% - 37.96% |
| cases | 60-70 | 8 | 8/80 ( 10 %) | 4.84% - 17.98% |
| cases | 80-90 | 1 | 1/80 ( 1.25 %) | 0.14% - 5.69% |
| control | 20-30 | 1 | 1/20 ( 5 %) | 0.54% - 21.08% |
| control | 30-40 | 3 | 3/20 ( 15 %) | 4.41% - 34.86% |
| control | 40-50 | 5 | 5/20 ( 25 %) | 10.24% - 46.42% |
| control | 50-60 | 11 | 11/20 ( 55 %) | 33.77% - 74.9% |
Table 5
| cases | control | |
|---|---|---|
| 20-30 | 2 | 1 |
| 30-40 | 21 | 3 |
| 40-50 | 26 | 5 |
| 50-60 | 22 | 11 |
| 60-70 | 8 | 0 |
| 80-90 | 1 | 0 |
Figure 2 Sex Distribution in Our Population
The Dodged bar chart above represents individual counts representing frequency of Sex categories MALE and FEMALE in categories cases and control belonging to group Group. Subgroup FEMALE has highest percentage 50/80 ( 62.5 % ) in group cases . Subgroup FEMALE has highest percentage 12/20 ( 60 % ) in group control . To formally check for association between groups we performed pearson chi-square test .
we found a Non-significant association between Sex and Group. The chi-square statistic was 0 . The degree of freedom was 1 and P value was 1 .Contingency and Proportion table are shown below
Table 6
| Group | Sex | n | value | 95 % Confidence Interval |
|---|---|---|---|---|
| cases | FEMALE | 50 | 50/80 ( 62.5 %) | 51.6% - 72.51% |
| cases | MALE | 30 | 30/80 ( 37.5 %) | 27.49% - 48.4% |
| control | FEMALE | 12 | 12/20 ( 60 %) | 38.39% - 78.94% |
| control | MALE | 8 | 8/20 ( 40 %) | 21.06% - 61.61% |
Table 7
| cases | control | |
|---|---|---|
| FEMALE | 50 | 12 |
| MALE | 30 | 8 |
Figure 3 Distribution Of smokers in Our Population
The Dodged bar chart above represents individual counts representing frequency of Smoking categories Smoker and Non-Smoker in categories cases and control . Subgroup Non-Smoker has highest percentage 65/80 ( 81.25 % ) in group cases . Subgroup Non-Smoker has highest percentage 15/20 ( 75 % ) in group control . To formally check for association between groups we performed pearson chi-square test .
we found a Non-significant association between Smoking and Group. The chi-square statistic was 0.1 . The degree of freedom was 1 and P value was 0.75 .Contingency and Proportion table are shown below
Table 8
| Group | Smoking | n | value | 95 % Confidence Interval |
|---|---|---|---|---|
| cases | Non-Smoker | 65 | 65/80 ( 81.25 %) | 71.67% - 88.61% |
| cases | Smoker | 15 | 15/80 ( 18.75 %) | 11.39% - 28.33% |
| control | Non-Smoker | 15 | 15/20 ( 75 %) | 53.58% - 89.76% |
| control | Smoker | 5 | 5/20 ( 25 %) | 10.24% - 46.42% |
Table 9
| cases | control | |
|---|---|---|
| Non-Smoker | 65 | 15 |
| Smoker | 15 | 5 |
Figure 3A Distribution Of PAD in Our Population
The Dodged bar chart above represents individual counts representing frequency of PAD categories PAD and NOT PAD in categories cases and control. Subgroup NOT PAD has highest percentage 48/80 ( 60 % ) in group cases . Subgroup NOT PAD has highest percentage 19/20 ( 95 % ) in group control . To formally check for association between groups we performed pearson chi-square test .
we found a Significant association between PAD and Group. The chi-square statistic was 7.35 . The degree of freedom was 1 and P value was 0.01 .Contingency and Proportion table are shown below
Table 8A
| Group | PAD | n | value | 95 % Confidence Interval |
|---|---|---|---|---|
| cases | NOT PAD | 48 | 48/80 ( 60 %) | 49.07% - 70.22% |
| cases | PAD | 32 | 32/80 ( 40 %) | 29.78% - 50.93% |
| control | NOT PAD | 19 | 19/20 ( 95 %) | 78.92% - 99.46% |
| control | PAD | 1 | 1/20 ( 5 %) | 0.54% - 21.08% |
Table 9A
| cases | control | |
|---|---|---|
| NOT PAD | 48 | 19 |
| PAD | 32 | 1 |
Figure 4 Boxplot Of Distribution Of ABPI in our Population
In this Figure we see Box plot of ABPI in : cases and control respectively .The individual jittered data points of ABPI are overlaid over transparent Boxplot for better visualisation. We see distribution of data in individual sub-groups based on these box-plots. The lower edge of box plot represents -first quartile (Q1), Horizontal bar represents the median, Upper edge represnts third quartile (Q3), Two black lines (whiskers) emanating from box-plots signify range of non-outlier data for the particular sub-group. Lower whisker represents minimum(Q1- 1.5 interquartile range) non-outlier limit of ABPI and upper whisker represnts maximum(Q1+1.5interquartile range) of ABPI .Any data beyond whiskers of box-plots represents outliers in the sub-groups The big brown point in the box-plots represents mean ABPI of 2 groups and it has been annotated in the figure itself Summary Statistics of the groups is presented in table below
Table 10 Summary Table Of ABPI within Groups
| Group | n | Mean | SD | Median | Minimum | Maximum |
|---|---|---|---|---|---|---|
| cases | 80 | 0.922 | 0.093 | 0.920 | 0.69 | 1.14 |
| control | 20 | 1.131 | 0.095 | 1.135 | 0.89 | 1.32 |
The mean in Group cases [ 0.92 ± 0.09 ] was significantly lower than Group control [ 1.13 ± 0.09 ] . The mean difference was -0.21 and 95 % confidence interval of the difference was ( -0.26 - -0.16 ) . The p value was <0.001 . The t statistic was -8.88 and degree of freedom of the Welch unpaired two-sample t test was 28.84 .In Formal statistical notation this result is expressed as : t(28.84) = -8.88, p= <0.001.. The detailed statistical parameters of T test are given in table below.
TABLE 11
| variable | group1 | group2 | statistic | df | p |
|---|---|---|---|---|---|
| ABPI | cases | control | -8.88 | 28.84 | <0.001 |
Figure 5 Barplot Of Age-Sex Distribution Of ABPI in our Population
Table 12 Age-Sex Distribution Of ABPI in our Population
| Group | age_grp | Sex | n | Mean ( ABPI ) | SD ( ABPI ) | Median ( ABPI ) |
|---|---|---|---|---|---|---|
| cases | 20-30 | FEMALE | 1 | 0.99 | 0.99 | |
| cases | 20-30 | MALE | 1 | 0.90 | 0.90 | |
| cases | 30-40 | FEMALE | 14 | 0.92 | 0.13 | 0.92 |
| cases | 30-40 | MALE | 7 | 0.91 | 0.08 | 0.91 |
| cases | 40-50 | FEMALE | 12 | 0.89 | 0.08 | 0.88 |
| cases | 40-50 | MALE | 14 | 0.89 | 0.07 | 0.88 |
| cases | 50-60 | FEMALE | 17 | 0.95 | 0.1 | 0.94 |
| cases | 50-60 | MALE | 5 | 0.94 | 0.07 | 0.93 |
| cases | 60-70 | FEMALE | 5 | 0.93 | 0.08 | 0.96 |
| cases | 60-70 | MALE | 3 | 1.03 | 0.04 | 1.04 |
| cases | 80-90 | FEMALE | 1 | 0.85 | 0.85 | |
| control | 20-30 | FEMALE | 1 | 1.13 | 1.13 | |
| control | 30-40 | FEMALE | 1 | 1.15 | 1.15 | |
| control | 30-40 | MALE | 2 | 1.12 | 0.12 | 1.12 |
| control | 40-50 | FEMALE | 3 | 1.06 | 0.16 | 1.08 |
| control | 40-50 | MALE | 2 | 1.17 | 0.04 | 1.17 |
| control | 50-60 | FEMALE | 7 | 1.17 | 0.09 | 1.14 |
| control | 50-60 | MALE | 4 | 1.10 | 0.09 | 1.07 |
Figure 6 Boxplot Of Distribution Of CRP in our Population
In this Figure we see Box plot of CRP in 2 sub-groups : cases and control respectively .The individual jittered data points of CRP are overlaid over transparent Boxplot for better visualisation. We see distribution of data in individual sub-groups of Group based on these box-plots. The lower edge of box plot represents -first quartile (Q1), Horizontal bar represents the median, Upper edge represnts third quartile (Q3), Two black lines (whiskers) emanating from box-plots signify range of non-outlier data for the particular sub-group. Lower whisker represents minimum(Q1- 1.5 interquartile range) non-outlier limit of CRP and upper whisker represnts maximum(Q1+1.5interquartile range) of CRP .Any data beyond whiskers of box-plots represents outliers in the sub-groups The big brown point in the box-plots represents mean CRP of 2 groups and it has been annotated in the figure itself We can see the statistical summary of Test while summary statistics of Effect size and its confidence Interval (represented as Hedges’s G ) at top of plot. Summary Statistics of the groups is presented in table below
Table 13 Summary Table Of CRP within Groups
| Group | n | Mean | SD | Median | Minimum | Maximum |
|---|---|---|---|---|---|---|
| cases | 80 | 8.000 | 3.001 | 7.925 | 1.80 | 16.15 |
| control | 20 | 2.099 | 0.699 | 1.965 | 1.07 | 3.53 |
The mean in Group cases [ 8 ± 3.0 ] was significantly higher than Group control [ 2.1 ± 0.7 ] . The mean difference was 5.9 and 95 % confidence interval of the difference was ( 5.17 - 6.64 ) . The p value was <0.001 . The t statistic was 15.94 and degree of freedom of the Welch unpaired two-sample t test was 97.85 .In Formal statistical notation this result is expressed as : t(97.85) = 15.94, p= <0.001.
TABLE 14
| variable | group1 | group2 | statistic | df | p |
|---|---|---|---|---|---|
| CRP | cases | control | 15.94 | 97.85 | <0.001 |
Figure 5 Barplot Of Age-Sex Distribution Of CRP in our Population
Table 15 Age-Sex Distribution Of CRP in our Population
| Group | age_grp | Sex | n | Mean ( CRP ) | SD ( CRP ) | Median ( CRP ) |
|---|---|---|---|---|---|---|
| cases | 20-30 | FEMALE | 1 | 12.40 | 12.40 | |
| cases | 20-30 | MALE | 1 | 5.30 | 5.30 | |
| cases | 30-40 | FEMALE | 14 | 7.74 | 3.5 | 6.76 |
| cases | 30-40 | MALE | 7 | 8.64 | 2.19 | 9.76 |
| cases | 40-50 | FEMALE | 12 | 7.62 | 3.18 | 7.89 |
| cases | 40-50 | MALE | 14 | 8.17 | 3.28 | 8.73 |
| cases | 50-60 | FEMALE | 17 | 8.22 | 3.39 | 7.45 |
| cases | 50-60 | MALE | 5 | 6.45 | 1.44 | 7.24 |
| cases | 60-70 | FEMALE | 5 | 8.93 | 2.52 | 9.48 |
| cases | 60-70 | MALE | 3 | 8.13 | 1.34 | 8.20 |
| cases | 80-90 | FEMALE | 1 | 6.60 | 6.60 | |
| control | 20-30 | FEMALE | 1 | 2.04 | 2.04 | |
| control | 30-40 | FEMALE | 1 | 1.98 | 1.98 | |
| control | 30-40 | MALE | 2 | 2.74 | 1.12 | 2.74 |
| control | 40-50 | FEMALE | 3 | 1.96 | 1.08 | 1.64 |
| control | 40-50 | MALE | 2 | 2.37 | 0.14 | 2.37 |
| control | 50-60 | FEMALE | 7 | 2.20 | 0.75 | 2.24 |
| control | 50-60 | MALE | 4 | 1.62 | 0.28 | 1.60 |
Figure showing Correlation between ABPI and CRP
The scatter plots above show relationship between CRP on X axis and ABPI on Y axis. Graphically, we see that as CRP increases, ABPI decreases . On a formal statistical linear regression analysis, we that line of best fit (blue line signifying line with least square difference) also has a negative slope implying a negative correlation. The gray shaded error around blue line signifies 95% confidence interval of linear regression line of best fit. The correlation between two variables is Significant . The Pearson’s correlation between CRP and ABPI is -0.26 with 95% Confidence Interval of -0.43 to -0.07. the t statistic is -2.65 The p value is 0.01 .The degree of freedom is 98. In formal statistical notation this expressed as t(98)= -2.65, P= 0.01. r(Pearson) = -0.26 95% C.I. [-0.43–0.07]. n= 100. The correlation is summmarised in table below
Table 16. Table Summarizing correlation between CRP and ABPI
| Group 1 | Group 2 | Degree of Freedom | T statistic | Correlation | 95 % C.I. | P value |
|---|---|---|---|---|---|---|
| CRP | ABPI | 98 | -2.65 | -0.26 | -0.43–0.07 | 0.01 |
Table 16 Table with summary statistics of CRP and ABPI
| variable | n | Mean | SD | Median | Minimum | Maximum |
|---|---|---|---|---|---|---|
| ABPI | 100 | 0.964 | 0.125 | 0.945 | 0.69 | 1.32 |
| CRP | 100 | 6.820 | 3.592 | 6.915 | 1.07 | 16.15 |
Figure showing Correlation between ABPI and HBA1C
he scatter plots above show relationship between HBA1C on X axis and ABPI on Y axis. Graphically, we see that as HBA1C increases, ABPI decreases . On a formal statistical linear regression analysis, we that line of best fit (blue line signifying line with least square difference) also has a negative slope implying a negative correlation. The gray shaded error around blue line signifies 95% confidence interval of linear regression line of best fit. The correlation between two variables is Significant . The Pearson’s correlation between HBA1C and ABPI is -0.56 with 95% Confidence Interval of -0.68 to -0.41. the t statistic is -6.77 The p value is <0.001 .The degree of freedom is 98. In formal statistical notation this expressed as t(98)= -6.77, P= <0.001. r(Pearson) = -0.56 95% C.I. [-0.68–0.41]. n= 100. The correlation is summmarised in table below
Table 17. Table Summarizing correlation between ABPI and HBA1c
| Group 1 | Group 2 | Degree of Freedom | T statistic | Correlation | 95 % C.I. | P value |
|---|---|---|---|---|---|---|
| HBA1C | ABPI | 98 | -6.77 | -0.56 | -0.68–0.41 | <0.001 |
Table 18 Table with summary statistics of ABPI and HBA1C
| variable | n | Mean | SD | Median | Minimum | Maximum |
|---|---|---|---|---|---|---|
| ABPI | 100 | 0.964 | 0.125 | 0.945 | 0.690 | 1.320 |
| HBA1C | 100 | 7.360 | 0.739 | 7.628 | 5.625 | 8.577 |
Figure showing Correlation between ABPI and LDL
The scatter plots above show relationship between LDL on X axis and ABPI on Y axis. Graphically, we see that as LDL increases, ABPI decreases . On a formal statistical linear regression analysis, we that line of best fit (blue line signifying line with least square difference) also has a negative slope implying a negative correlation. The gray shaded error around blue line signifies 95% confidence interval of linear regression line of best fit. The correlation between two variables is Significant . The Pearson’s correlation between LDL and ABPI is -0.54 with 95% Confidence Interval of -0.67 to -0.39. the t statistic is -6.38 The p value is <0.001 .The degree of freedom is 98. In formal statistical notation this expressed as t(98)= -6.38, P= <0.001. r(Pearson) = -0.54 95% C.I. [-0.67–0.39]. n= 100. The correlation is summmarised in table below
Table 19. Table Summarizing correlation between ABPI and LDL
| Group 1 | Group 2 | Degree of Freedom | T statistic | Correlation | 95 % C.I. | P value |
|---|---|---|---|---|---|---|
| ABPI | LDL | 98 | -6.38 | -0.54 | -0.67–0.39 | <0.001 |
Table 20 Table with summary statistics of ABPI and LDL
| variable | n | Mean | SD | Median | Minimum | Maximum |
|---|---|---|---|---|---|---|
| ABPI | 100 | 0.964 | 0.125 | 0.945 | 0.69 | 1.32 |
| LDL | 100 | 152.000 | 29.671 | 162.000 | 77.00 | 199.00 |
Figure showing Correlation between ABPI and ASCVD
The scatter plots above show relationship between ASCVD on X axis and ABPI on Y axis. Graphically, we see that as ASCVD increases, ABPI decreases . On a formal statistical linear regression analysis, we that line of best fit (blue line signifying line with least square difference) also has a negative slope implying a negative correlation. The gray shaded error around blue line signifies 95% confidence interval of linear regression line of best fit. The correlation between two variables is Significant . The Pearson’s correlation between ASCVD and ABPI is -0.55 with 95% Confidence Interval of -0.68 to -0.4. the t statistic is -6.58 The p value is <0.001 .The degree of freedom is 98. In formal statistical notation this expressed as t(98)= -6.58, P= <0.001. r(Pearson) = -0.55 95% C.I. [-0.68–0.4]. n= 100. The correlation is summmarised in table below
Table 21. Table Summarizing correlation between ABPI and ASCVD
| Group 1 | Group 2 | Degree of Freedom | T statistic | Correlation | 95 % C.I. | P value |
|---|---|---|---|---|---|---|
| ABPI | ASCVD | 98 | -6.58 | -0.55 | -0.68–0.4 | <0.001 |
Table 22 Table with summary statistics of ASCVD and ABPI
| variable | n | Mean | SD | Median | Minimum | Maximum |
|---|---|---|---|---|---|---|
| ABPI | 100 | 0.964 | 0.125 | 0.945 | 0.69 | 1.32 |
| ASCVD | 100 | 7.840 | 2.498 | 8.660 | 2.78 | 11.75 |
Table 23 Correlation table of Selected variables TSH,LDL,T3,T4,TC,HDL,LDL,TG,LipoproteinA,ASCVD,HbA1c with their confidence intervals
| Variable1 | Variable2 | Correlation | pvalue | significance | Confidence_Interval |
|---|---|---|---|---|---|
| LDL | Total_Cholesterol | 0.99 | <0.001 | Significant | 0.98-0.99 |
| TG | HBA1C | 0.93 | <0.001 | Significant | 0.89-0.95 |
| LDL | HBA1C | 0.92 | <0.001 | Significant | 0.89-0.95 |
| TG | Total_Cholesterol | 0.92 | <0.001 | Significant | 0.88-0.95 |
| Total_Cholesterol | HBA1C | 0.92 | <0.001 | Significant | 0.88-0.94 |
| LDL | TG | 0.90 | <0.001 | Significant | 0.85-0.93 |
| ASCVD | HBA1C | 0.87 | <0.001 | Significant | 0.81-0.91 |
| SBP | DBP | 0.86 | <0.001 | Significant | 0.8-0.9 |
| ASCVD | Total_Cholesterol | 0.84 | <0.001 | Significant | 0.77-0.89 |
| ASCVD | TG | 0.84 | <0.001 | Significant | 0.76-0.89 |
| ASCVD | LDL | 0.83 | <0.001 | Significant | 0.76-0.88 |
| HDL | HBA1C | -0.83 | <0.001 | Significant | -0.88–0.75 |
| LDL | HDL | -0.79 | <0.001 | Significant | -0.86–0.71 |
| HDL | TG | -0.79 | <0.001 | Significant | -0.85–0.7 |
| DBP | HBA1C | 0.78 | <0.001 | Significant | 0.69-0.85 |
| DBP | LDL | 0.76 | <0.001 | Significant | 0.66-0.83 |
| DBP | Total_Cholesterol | 0.76 | <0.001 | Significant | 0.66-0.83 |
| DBP | TG | 0.74 | <0.001 | Significant | 0.63-0.81 |
| HDL | Total_Cholesterol | -0.72 | <0.001 | Significant | -0.81–0.61 |
| ASCVD | DBP | 0.70 | <0.001 | Significant | 0.58-0.79 |
| ASCVD | HDL | -0.67 | <0.001 | Significant | -0.77–0.55 |
| SBP | HBA1C | 0.67 | <0.001 | Significant | 0.54-0.76 |
| CRP | Total_Cholesterol | 0.65 | <0.001 | Significant | 0.52-0.75 |
| CRP | LDL | 0.65 | <0.001 | Significant | 0.51-0.75 |
| CRP | ASCVD | 0.64 | <0.001 | Significant | 0.51-0.74 |
| CRP | HBA1C | 0.64 | <0.001 | Significant | 0.5-0.74 |
| DBP | HDL | -0.63 | <0.001 | Significant | -0.74–0.5 |
| SBP | Total_Cholesterol | 0.61 | <0.001 | Significant | 0.47-0.72 |
| SBP | LDL | 0.61 | <0.001 | Significant | 0.47-0.72 |
| SBP | TG | 0.61 | <0.001 | Significant | 0.47-0.72 |
| CRP | TG | 0.61 | <0.001 | Significant | 0.47-0.72 |
| ASCVD | SBP | 0.59 | <0.001 | Significant | 0.45-0.71 |
| CRP | DBP | 0.57 | <0.001 | Significant | 0.42-0.69 |
| ABPI | HBA1C | -0.56 | <0.001 | Significant | -0.68–0.41 |
| ABPI | ASCVD | -0.55 | <0.001 | Significant | -0.68–0.4 |
| ABPI | Total_Cholesterol | -0.55 | <0.001 | Significant | -0.67–0.39 |
| ABPI | LDL | -0.54 | <0.001 | Significant | -0.67–0.39 |
| CRP | SBP | 0.53 | <0.001 | Significant | 0.37-0.66 |
| SBP | HDL | -0.51 | <0.001 | Significant | -0.65–0.35 |
| ABPI | TG | -0.50 | <0.001 | Significant | -0.63–0.34 |
| CRP | HDL | -0.50 | <0.001 | Significant | -0.63–0.33 |
| ABPI | DBP | -0.46 | <0.001 | Significant | -0.61–0.3 |
| ABPI | SBP | -0.41 | <0.001 | Significant | -0.56–0.23 |
| ABPI | HDL | 0.39 | <0.001 | Significant | 0.21-0.55 |
| ABPI | CRP | -0.26 | 0.00945 | Significant | -0.43–0.07 |
Multiple linear regression was conducted to find best combination of HBA1C,Age,SexMALE,LDL,TG & CRP for predicting ABPI . Dummy indicator(0/1) were used for categorical variables. The Forest plot above shows standardized regression coefficients of HBA1C,Age,SexMALE,LDL,TG & CRP with their confidence intervals as horizontal error bars on X axis. An error bar which crosses vertical line of zero in this plot is non-significant.
We fitted a linear model (estimated using OLS) to predict ABPI with HBA1C, Age, Sex, LDL, TG and CRP (formula = ABPI ~ HBA1C + Age + Sex + LDL + TG + CRP). Standardized parameters were obtained by fitting the model on a standardized version of the dataset. Effect sizes were labelled following Funder's (2019) recommendations.
The model explains a significant and substantial proportion of variance (R2 = 0.36, F(6, 93) = 8.86, p < .001, adj. R2 = 0.32). The model's intercept, corresponding to ABPI = 0, HBA1C = 0, Age = 0, Sex = , LDL = 0, TG = 0 and CRP = 0, is at 1.66 (SE = 0.19, 95% CI [1.29, 2.03[, std. intercept = 0.02, p < .001). Within this model:
- The effect of HBA1C is negative and can be considered as medium and significant (beta = -0.10, SE = 0.04, 95% CI [-0.19, -0.01[, std. beta = -0.60, p < .05).
- The effect of Age is positive and can be considered as very small and not significant (beta = 0.00, SE = 0.00, 95% CI [0.00, 0.00[, std. beta = 0.12, p > .1).
- The effect of Sex (MALE) is negative and can be considered as tiny and not significant (beta = -0.01, SE = 0.02, 95% CI [-0.05, 0.04[, std. beta = -0.05, p > .1).
- The effect of LDL is negative and can be considered as small and not significant (beta = 0.00, SE = 0.00, 95% CI [0.00, 0.00[, std. beta = -0.29, p > .1).
- The effect of TG is positive and can be considered as very small and not significant (beta = 0.00, SE = 0.00, 95% CI [0.00, 0.00[, std. beta = 0.19, p > .1).
- The effect of CRP is positive and can be considered as very small and not significant (beta = 0.01, SE = 0.00, 95% CI [0.00, 0.01[, std. beta = 0.20, p = 0.08).
Table 24. Regression Table
| Parameter | Coefficient | CI_low | CI_high | p | Std_Coefficient | Fit |
|---|---|---|---|---|---|---|
| (Intercept) | 1.662 | 1.292 | 2.033 | 0 | 0.018 | |
| HBA1C | -0.101 | -0.19 | -0.012 | 0.026 | -0.598 | |
| Age | 0.002 | -0.001 | 0.004 | 0.143 | 0.123 | |
| SexMALE | -0.006 | -0.048 | 0.037 | 0.787 | -0.046 | |
| LDL | -0.001 | -0.003 | 0.001 | 0.213 | -0.288 | |
| TG | 0.001 | -0.001 | 0.002 | 0.416 | 0.187 | |
| CRP | 0.007 | -0.001 | 0.014 | 0.075 | 0.197 | |
| R2 | 0.364 | |||||
| R2 (adj.) | 0.323 |
The combination of these predictors significantly predicted ABPI .There were 100 observations in our model. The number of predictors in model was 6 ,while degree of freedom of residuals(no.of observation-number Of predictors in model) was 93. In statistical notation this is expressed as F(6,93) = 8.86, P = <0.001 .The standard deviation of residual error was 0.1 implying ABPI was predicted with average accuracy of +- 0.1 by our model. The adjusted R - Square for our model is 0.32 implying our model predicts 32.27 percentage variation in ABPI .
In Our Multivariable linear regression Model,On adjusting for all variables , HBA1C significantly predicted ABPI .
Our Final regression equation was predicted ABPI = 1.6 -0.1HBA1C +0.002Age -0.006SexMALE -0.001LDL +0.0001TG +0.0007CRP
Interpretation
1 unit change in HBA1C leads to 0.1 decrease in ABPI . Rest of values are not Significant.
Table 25 Univariable and Multivariable Regression coefficients
| Dependent: ABPI | Mean (sd) | Coefficient (univariable) | Coefficient (multivariable) | |
|---|---|---|---|---|
| HBA1C | [5.62,8.58] | 1.0 (0.1) | -0.096 (-0.124 to -0.068, p<0.0001) | -0.101 (-0.190 to -0.012, p=0.0263) |
| Age | [27,82] | 1.0 (0.1) | 0.001 (-0.001 to 0.004, p=0.2469) | 0.002 (-0.001 to 0.004, p=0.1429) |
| Sex | FEMALE | 1.0 (0.1) |
|
|
| MALE | 1.0 (0.1) | -0.003 (-0.055 to 0.048, p=0.8965) | -0.006 (-0.048 to 0.037, p=0.7872) | |
| LDL | [77,199] | 1.0 (0.1) | -0.002 (-0.003 to -0.002, p<0.0001) | -0.001 (-0.003 to 0.001, p=0.2130) |
| TG | [101,264] | 1.0 (0.1) | -0.002 (-0.002 to -0.001, p<0.0001) | 0.001 (-0.001 to 0.002, p=0.4163) |
| CRP | [1.07,16.1] | 1.0 (0.1) | -0.009 (-0.016 to -0.002, p=0.0095) | 0.007 (-0.001 to 0.014, p=0.0754) |