Table 1

Selected respondent and Medicare-data linkage characteristics stratified by middle age LTPA status

Middle age leisure time physical activityOverall<1
hour/week
1–3
hours/week
4–7
hours/week
>7
hours/week
N (%)21 750 (100.0)4916 (22.6)5635 (25.9)5774 (26.5)5425 (24.9)
Sociodemographic characteristics
Mean age, years (SD)59.9 (3.2)59.7 (3.2)59.7 (3.2)59.9 (3.2)60.1 (3.1)
White, non-Hispanic (%)94.893.394.595.695.6
Male (%)54.255.254.553.753.7
Married (%)72.369.472.172.974.3
Education level (%)
 <11 years schooling21.823.720.620.723.4
 High school34.435.633.933.934.4
 College degree41.939.143.944.239.9
Health behavior characteristics
Smoking history (%)
 Never smoker38.036.638.438.638.1
 Former smoker47.245.246.648.248.5
 Current smoker11.914.912.210.510.4
BMI category at age 18 (%)
 BMI <25.0 kg/m283.081.283.083.484.2
 25.0 ≤BMI < 30.0 kg/m29.110.18.99.18.6
 BMI ≥30.0 kg/m21.42.21.41.11.0
BMI category at age ~60 (%)
 BMI <25.0 kg/m237.328.734.240.644.8
 25.0 ≤BMI < 30.0 kg/m241.039.542.142.339.9
 BMI ≥30.0 kg/m220.230.122.015.914.0
Television viewing (%)
 0–2 hours/day36.132.635.437.738.5
 3–4 hours/day45.445.146.945.344.2
 5+ hours/day18.222.117.516.817.0
Clinical characteristics
Self-reported health status (%)
 Excellent/very good58.545.655.362.269.7
 Good33.441.536.331.625.2
 Fair7.011.97.15.34.3
Self-reported clinical history (%)
 Any health problem34.239.734.132.331.6
 Heart disease9.910.710.09.79.2
 Diabetes6.69.76.65.54.8
 Osteoporosis2.72.82.92.82.6
 Stroke1.01.50.81.00.9
Medicare data characteristics
Reason for linkage (%)
 Consented alive87.584.188.488.389.0
 Dead12.515.911.611.711.0
Mean age at Medicare entry, years (SD)65.0 (0.1)65.0 (0.1)65.0 (0.1)65.0 (0.1)65.0 (0.1)
Years of Medicare data (SD)6.2 (2.9)5.8 (2.8)6.2 (3.1)6.4 (3.1)6.7 (3.1)
  • Column percentage may not total 100% because of ‘unknown’ category response. See online supplemental appendix table S1 for full distributions. χ2 statistics (χ) for table 1 with p<0.001 when stratifying by middle age LTPA except for sex (p=0.203) heart disease (p=0.047); osteoporosis (p=0.790) stroke (p=0.004). The analytical sample had a mean of 6.2 years of Medicare coverage (range 1–10 years) with an unadjusted average annual healthcare cost of US$7813 during this time period. The <1 hour/week is based on respondents that responded never, rarely, or <1 hour/week when asked how often they participated in moderate and vigorous activities in middle age.

  • BMI, body mass index; LTPA, long-term leisure time physical activity.