Table 2.
Descriptive statistics by change in walkability between baseline (2000-2001) and follow-up (2005-2006) exams, n=1,079 middle-aged adults who moved residential locations between exams
| Groups by change in walkability index |
|||||
|---|---|---|---|---|---|
| Characteristics | All participants (n=1,079) | Decrease (n=394)a | Minimal change (n=510)b | Increase (n=175)c | p |
| Built environment variables | |||||
| Walkability index at baseline | 20.14 (7.70) | 23.24 (7.14) | 19.14 (6.95) | 16.07 (8.37) | 0.00*** |
| Change in walkability index | −2.09 (7.04) | −8.99 (4.87) | −0.19 (1.75) | 7.91 (5.09) | — |
| Moved for built environment (%) | 58.85 | 54.06 | 62.35 | 59.43 | 0.04** |
| Health outcomes at baseline | |||||
| Physical activity from walking | |||||
| Participation (%) | 75.72 | 76.65 | 73.33 | 80.57 | 0.14 |
| Exercise units | 49.31 (50.59) | 49.26 (50.48) | 49.44 (51.88) | 49.05 (47.18) | 0.99 |
| Body mass index, kg/m2 | 28.41 (6.50) | 28.12 (6.41) | 28.34 (6.47) | 29.27 (6.78) | 0.14 |
| Waist circumference, cm | 88.79 (15.01) | 88.44 (14.63) | 88.51 (15.40) | 90.43 (14.68) | 0.29 |
| Systolic blood pressure, mmHg | 112.24 (13.69) | 111.00 (12.81) | 112.92 (14.22) | 113.07 (13.78) | 0.08* |
| HOMA-IR (insulin resistance) d | 2.21 (1.66) | 2.14 (1.42) | 2.25 (1.86) | 2.22 (1.51) | 0.60 |
| Triglycerides, mg/dL | 95.37 (57.22) | 95.81 (58.71) | 93.93 (56.49) | 98.57 (56.08) | 0.64 |
| LDL cholesterol, mg/dL | 113.44 (33.90) | 113.17 (33.08) | 112.76 (35.39) | 116.03 (31.24) | 0.53 |
| HDL cholesterol, mg/dL | 51.29 (14.49) | 51.18 (14.46) | 51.43 (14.63) | 51.15 (14.23) | 0.96 |
| C-reactive protein, ug/mL | 3.11 (5.06) | 2.77 (3.91) | 3.35 (6.00) | 3.16 (4.27) | 0.23 |
| Atherogenic dyslipidemia (%) | 9.27 | 10.15 | 8.43 | 9.71 | 0.66 |
| Change in health outcomes | |||||
| Change in walking participation | 0.32 | ||||
| Started participating (%) | 10.84 | 11.17 | 11.96 | 6.86 | |
| Stopped participating (%) | 15.48 | 16.75 | 14.90 | 14.29 | |
| Change in walking exercise units | −0.37 (56.60) | −3.72 (55.38) | 2.07 (57.96) | 0.02 (55.20) | 0.31 |
| Change in body mass index, kg/m2 | 0.78 (2.83) | 0.90 (2.49) | 0.72 (2.81) | 0.66 (3.54) | 0.54 |
| Change in waist circumference, cm | 2.68 (8.28) | 2.91 (8.49) | 2.50 (8.14) | 2.71 (8.22) | 0.76 |
| Change in systolic blood pressure, mmHg | 4.02 (13.07) | 4.95 (12.47) | 3.77 (14.00) | 2.62 (11.37) | 0.12 |
| Change in HOMA-IR d | 0.23 (1.57) | 0.32 (1.51) | 0.18 (1.67) | 0.13 (1.40) | 0.31 |
| Change in triglycerides, mg/dL | 6.02 (50.30) | 8.93 (53.21) | 4.21 (49.49) | 4.74 (45.65) | 0.35 |
| Change in LDL cholesterol, mg/dL | −2.88 (26.82) | −0.16 (24.30) | −6.13 (29.09) | 0.44 (24.23) | 0.00*** |
| Change in HDL cholesterol, mg/dL | 3.42 (10.20) | 3.18 (10.02) | 3.73 (10.59) | 3.08 (9.43) | 0.64 |
| Change in C-reactive protein, ug/mL | −0.37 (5.09) | −0.30 (3.14) | −0.73 (5.16) | 0.52 (7.70) | 0.02** |
| Change in atherogenic dyslipidemia | 0.58 | ||||
| New case (%) | 5.38 | 5.33 | 4.90 | 6.86 | |
| Removed case (%) | 5.00 | 6.09 | 4.12 | 5.14 | |
| Covariates at baseline | |||||
| Age, in years | 39.67 (3.68) | 39.74 (3.66) | 39.64 (3.71) | 39.55 (3.66) | 0.84 |
| Female (%) | 54.77 | 53.81 | 55.69 | 54.29 | 0.85 |
| Race/ethnicity | 0.41 | ||||
| Black, not Hispanic (%) | 50.88 | 48.48 | 52.94 | 50.29 | |
| White, not Hispanic (%) | 49.12 | 51.52 | 47.06 | 49.71 | |
| More than high school (vs. less/equal) (%) | 58.20 | 58.12 | 59.02 | 56.00 | 0.78 |
| Income, in thousands | 62.51 (38.86) | 62.67 (37.84) | 63.02 (39.45) | 60.63 (39.58) | 0.78 |
| Household size | 3.04 (1.61) | 2.96 (1.47) | 3.15 (1.71) | 2.89 (1.60) | 0.08* |
| Currently married (%) | 46.80 | 46.70 | 48.82 | 41.14 | 0.21 |
| Currently working (%) | 85.82 | 86.55 | 86.27 | 82.86 | 0.47 |
| Current smoker (%) | 23.63 | 23.86 | 23.73 | 22.86 | 0.97 |
| Health problems (%) | 14.55 | 12.94 | 15.10 | 16.57 | 0.47 |
| On medication(s) for hypertension (%) | 6.58 | 5.33 | 7.45 | 6.86 | 0.44 |
| On medication(s) for cholesterol (%) | 1.11 | 1.02 | 0.98 | 1.71 | 0.71 |
| Change in covariates, as applicable | |||||
| Change in income | 5.82 (28.54) | 8.06 (26.19) | 6.42 (28.46) | −0.99 (32.66) | 0.00*** |
| Change in household size | −0.18 (1.46) | −0.10 (1.35) | −0.20 (1.53) | −0.28 (1.50) | 0.33 |
| Change in marital status | 0.01** | ||||
| New marriage (%) | 10.75 | 12.94 | 10.59 | 6.29 | |
| No longer married (%) | 8.90 | 6.85 | 8.63 | 14.29 | |
| Change in employment status | 0.70 | ||||
| Started working (%) | 6.12 | 6.09 | 5.49 | 8.00 | |
| Stopped working (%) | 11.49 | 12.44 | 11.37 | 9.71 | |
| Change in smoking status | 0.06* | ||||
| Started smoking (%) | 2.59 | 1.52 | 2.35 | 5.71 | |
| Stopped smoking (%) | 4.82 | 4.82 | 5.49 | 2.86 | |
| Change in health problems | 0.87 | ||||
| New problems (%) | 9.55 | 10.41 | 8.82 | 9.71 | |
| No longer problems (%) | 9.27 | 8.38 | 9.61 | 10.29 | |
| Change in medication use | |||||
| Started hypertension meds. (%) | 9.09 | 8.40 | 9.02 | 10.86 | 0.35 |
| Started cholesterol meds. (%) | 6.58 | 6.35 | 8.04 | 2.86 | 0.11 |
LDL = low-density lipoprotein, HDL = high-density lipoprotein, HOMA-IR = homeostasis model assessment of insulin resistance
*
significant at 90% confidence
**
significant at 95% confidence
***
significant at 99% confidence
Groups are based on change in walkability, with cut points set at ± 0.5 SD of the change variable (+3.52 and −3.52)
a
Decrease: change in walkability ranges from −35.95 to −3.53
b
Minimal change in walkability ranges from −3.50 to 3.51
c
Increase: change in walkability ranges from 3.58 to 40.88
d
Participants with diabetes at baseline (n=42) excluded from HOMA-IR calculation