Table 1.
Sample characteristics (weighted) by social network index, NHANES III 1988–1994
| Social network index (SNI), mean (SD) or % |
||||||
|---|---|---|---|---|---|---|
| All (N = 1,075) | 4 (High) (N = 207) |
3 (N = 374) | 2 (N = 304) | 0–1(Low) (N = 190) |
p valuec | |
| Markers of inflammation | ||||||
| C-reactive protein (mg/dL) | 0.51 (0.81) | 0.42 (0.46) | 0.59 (1.07) | 0.46 (0.61) | 0.56 (0.78) | .049 |
| Plasma fibrinogen (mg/dL) | 315.87 (87.37) | 307.80 (62.00) | 317.93 (91.95) | 314.94 (94.81) | 325.10 (94.41) | .007 |
| Serum albumin (ug/mL) | 4.08 (0.37) | 4.08 (0.30) | 4.04 (0.41) | 4.10 (0.34) | 4.13 (0.39) | .144 |
| Inflammation burden Index | ||||||
| 0 | 47.21 | 51.98 | 45.90 | 48.35 | 41.14 | |
| 1 | 32.34 | 34.38 | 32.38 | 29.23 | 34.65 | .001 |
| 2 | 13.96 | 11.54 | 14.61 | 14.56 | 15.00 | |
| 3 | 6.49 | 2.11 | 7.10 | 7.86 | 9.21 | |
| Demographic and social factors | ||||||
| Age | 64.69 (12.64) | 64.58 (11.76) | 63.84 (12.71) | 64.49 (12.92) | 67.35 (12.90) | <.001 |
| Sex (1 = male) | 42.3 | 45.46 | 38.27 | 44.53 | 47.29 | .186 |
| Race (1 = nonwhite) | 5.24 | 3.05 | 5.81 | 7.12 | 6.6 | .278 |
| Education | 12.27 (3.25) | 13.55 (2.77) | 12.47 (2.95) | 11.77 (3.43) | 10.67 (3.41) | <.001 |
| Family income (in thousands) | 26.18 (13.59) | 28.75 (11.48) | 27.77 (13.75) | 24.65 (13.92) | 22.61 (13.68) | <.001 |
| Health behaviors | ||||||
| Cigarette smoking (never) | 40.76 | 36.58 | 48.12 | 36.92 | 32.97 | |
| Former | 43.32 | 53.47 | 39.07 | 40.1 | 41.98 | <.001 |
| Current | 15.92 | 9.94 | 12.82 | 22.98 | 25.06 | |
| Alcohol drinking (1 = none) | 56.47 | 43.26 | 63.76 | 54.61 | 57.85 | <.001 |
| Physical activitya (1 = none) | 27.1 | 19.00 | 21.88 | 32.98 | 42.64 | <.001 |
| Body mass index (BMI) | 26.61 (5.14) | 26.69 (4.37) | 26.32 (4.75) | 26.67 (5.74) | 27.13 (5.94) | .823 |
| Obesity (≥30 kg/m2) | 22.32 | 19.52 | 20.73 | 24.19 | 29.69 | .109 |
| Health status and medication | ||||||
| Number of chronic illnessesb | 1.60 (1.45) | 1.33 (1.19) | 1.67 (1.49) | 1.61 (1.55) | 1.83 (1.51) | .075 |
| Self-rated health (1 = poor; 5 = excellent) |
2.22 (1.11) | 2.52 (1.07) | 2.22 (1.04) | 2.21 (1.12) | 1.76 (1.17) | <.001 |
| Cholesterol medication (1 = yes) | 6.92 | 10.17 | 6.33 | 7.07 | 3.94 | .146 |
Notes:
a
Physical activities include jogging, biking, swimming, doing aerobics, dancing, doing exercises, doing garden work, lifting weights, or other exercises.
b
Includes 13 self-reported chronic illnesses: angina, arthritis, asthma, bronchitis, diabetes, emphysema, heart attack, heart failure, stroke, hip fracture, osteoporosis, spine fracture, and wrist fracture.
c
from χ2 test for difference in means between individuals with high to low levels of SNI.