Table 5.
Waist-to-hip ratio and incidence and hazard ratios (95%CI) of ischemic stroke by race and sex, ARIC, 1987-2005
| Quintile | Q1 | Q2 | Q3 | Q4 | Q5 | Trend p | HR1 | HR2 |
|---|---|---|---|---|---|---|---|---|
| Range (median) | 0.49- <0.87 (0.82) | 0.87- <0.91 (0.89) | 0.91- <0.94 (0.93) | 0.94- <0.98 (0.96) | 0.99- <1.39 (1.01) | |||
| Black women | ||||||||
| n of cases/N | 33/781 | 29/398 | 26/359 | 27/393 | 46/399 | |||
| incidence rate | 2.6 | 4.7 | 4.7 | 4.5 | 8.2 | |||
| Age-adjusted | 1 (Reference) | 1.71 (1.04-2.81) | 1.61 (0.96-2.70) | 1.61 (0.97-2.67) | 2.75 (1.75-4.33) | <0.001 | 1.34 (1.15-1.57) | 1.38 (1.16-1.63) |
| Model I | 1 (Reference) | 1.64 (1.00-2.71) | 1.46 (0.87-2.45) | 1.46 (0.88-2.44) | 2.45 (1.55-3.87) | <0.001 | 1.29 (1.10-1.51) | 1.32 (1.11-1.57) |
| Model II | 1 (Reference) | 1.20 (0.71-2.02) | 1.09 (0.64-1.85) | 0.88 (0.52-1.51) | 1.17 (0.72-1.91) | 0.87 | 0.96 (0.81-1.14) | 0.99 (0.83-1.20) |
| Black men | ||||||||
| n of cases/N | 5/126 | 13/279 | 30/345 | 31/341 | 24/273 | |||
| incidence rate | 2.7 | 3.1 | 5.9 | 6.2 | 6.4 | |||
| Age-adjusted | 1 (Reference)* | 1.92 (1.07-3.45) | 2.00 (1.12-3.58) | 1.98 (1.07-3.68) | 0.027 | 1.42 (1.08-1.88) | 1.39 (1.04-1.87) | |
| Model I | 1 (Reference) | 1.91 (1.06-3.44) | 1.92 (1.07-3.46) | 1.69 (0.91-3.15) | 0.098 | 1.32 (1.00-1.74) | 1.28 (0.96-1.72) | |
| Model II | 1 (Reference) | 1.65 (0.88-3.09) | 1.28 (0.66-2.50) | 1.03 (0.51-2.06) | 0.80 | 0.98 (0.72-1.35) | 0.97 (0.69-1.36) | |
| White women | ||||||||
| n of cases/N | 38/2,071 | 20/971 | 23/800 | 24/779 | 31/668 | |||
| incidence rate | 1.1 | 1.3 | 1.7 | 1.9 | 3.0 | |||
| Age-adjusted | 1 (Reference) | 1.04 (0.61-1.77) | 1.27 (0.75-2.13) | 1.25 (0.74-2.10) | 1.90 (1.17-3.10) | 0.013 | 1.30 (1.09-1.55) | 1.31 (1.09-1.57) |
| Model I | 1 (Reference) | 1.00 (0.58-1.70) | 1.19 (0.71-2.02) | 1.20 (0.71-2.02) | 1.76 (1.08-2.88) | 0.029 | 1.27 (1.06-1.52) | 1.28 (1.06-1.54) |
| Model II | 1 (Reference) | 0.85 (0.50-1.47) | 0.83 (0.48-1.44) | 0.77 (0.44-1.33) | 0.93 (0.54-1.60) | 0.68 | 1.01 (0.83-1.23) | 1.01 (0.82-1.24) |
| White men | ||||||||
| n of cases/N | 3/129 | 10/424 | 22/895 | 62/1,455 | 101/1,663 | |||
| incidence rate | 1.4 | 1.5 | 1.5 | 2.7 | 4.0 | |||
| Age-adjusted | 1 (Reference)* | 1.06 (0.53-2.10) | 1.82 (1.00-3.30) | 2.48 (1.39-4.41) | <0.001 | 1.69 (1.41-2.04) | 1.87 (1.47-2.38) | |
| Model I | 1 (Reference) | 1.09 (0.55-2.16) | 1.87 (1.03-3.41) | 2.55 (1.42-4.57) | <0.001 | 1.70 (1.41-2.06) | 1.88 (1.47-2.40) | |
| Model II | 1 (Reference) | 1.04 (0.52-2.08) | 1.62 (0.88-2.99) | 1.96 (1.07-3.60) | 0.0036 | 1.49 (1.21-1.84) | 1.61 (1.24-2.10) | |
HR denotes hazard ratio; CI, confidence interval.
Model I: Adjusted for age, education, smoking status, pack years, usual ethanol consumption, and physical activity.
Model II: Model I + systolic blood pressure, hypertension medication, diabetes, and blood levels of high density lipoprotein cholesterol, von Willebrand factor and albumin.
Trend test was performed by assigning the median value of each quintile to corresponding individuals and treating it as a continuous variable in the model.
HR1: HR per 1 standard deviation (0.078) increment of waist-to-hip ratio.
HR2: HR per 0.078 increment of waist-to-hip ratio with sample truncated at the 1st and 99th percentile (n=13,012).
: The lowest two categories were collapsed.