Table 3.

Adjusted Odds Ratios^a for Prevalent Frailty States by CMV IgG Antibody Concentration, Effect-Modified by IL-6 Concentration, Women's Health and Aging Studies I and II, Baltimore, Maryland, 1992–2002

Tertile of Plasma IL-6 Concentrationb	Frailty Status	CMV IgG Antibody Concentration, IU/mLc
		≤1.20 (n = 92)	1.21–10.16 (n = 140)		10.17–14.55 (n = 128)		14.56–18.16 (n = 129)		18.17–150 (n = 143)
		OR	OR	95% CI	OR	95% CI	OR	95% CI	OR	95% CI
First	Prefrail	1.00	1.20	0.50, 2.86	1.47	0.61, 3.51	0.79	0.31, 2.01	1.10	0.47, 2.55
	Frail	1.00	1.44	0.29, 7.11	2.24	0.46, 10.86	0.62	0.12, 3.16	1.77	0.38, 8.32
Second	Prefrail	1.00	1.30	0.66, 2.54	1.39	0.72, 2.67	1.21	0.62, 2.38	1.84	0.94, 3.57
	Frail	1.00	0.59	0.15, 2.34	1.72	0.52, 5.69	1.09	0.33, 3.56	2.92	0.95, 9.04
Third	Prefrail	1.00	1.42	0.59, 3.41	1.31	0.57, 2.97	1.96	0.86, 4.44	3.30	1.41, 7.70
	Frail	1.00	0.21	0.02, 1.87	1.28	0.22, 7.46	2.06	0.38, 11.17	5.18	0.99, 27.05

Abbreviations: CI, confidence interval; CMV, cytomegalovirus; IgG, immunoglobulin G; IL-6, interleukin-6; OR, odds ratio.

^aOdds ratios were derived from a multinomial logistic regression model, adjusting for age, race, high school education, coverage by private medical insurance, pack-years of smoking, cardiovascular disease (angina, myocardial infarction, congestive heart failure, peripheral artery disease, or stroke), and diabetes mellitus, and modeling for effect modification by plasma IL-6 concentration. Comparisons were made with participants whose CMV IgG antibody concentration was ≤1.20 IU/mL. The reference category was “nonfrail.”

^bPlasma IL-6 concentration was modeled as a continuous variable. Odds ratios were derived by setting IL-6 to the midpoints (medians) of each indicated tertile, the respective values of which were 1.62, 2.69, and 4.81 pg/mL.

^cA baseline CMV IgG antibody concentration of >1.20 IU/mL was considered seropositive, reflecting prior CMV infection.