The following exclusions were made: 1738 women with diagnosis of cancer (except nonmelanoma skin cancer) before baseline in 1997, 89 women with cataract extraction before 1997, 1788 women who moved away from the geographical study area between 1987 and 15 September 1997, and 1751 women with missing information on supplement use status. To avoid influence from changes in dietary habits and in use of dietary supplements due to prevalent chronic disease, we excluded women who, before baseline, reported or were hospitalized with (identified through inpatient registers) diabetes (n = 1040), high blood pressure (n = 5538), and cardiovascular disorders (n = 2447). After these exclusions, the study cohort included 24,593 women
TABLE 2
Association (with 95% CI) between dietary supplement use and surgical cataract extraction in Swedish women (n = 24,593)1
Dietary supplement use
No supplement use
(n = 9974)
Only vitamin C
(n = 1225)2
Only multivitamins
(n = 2259)3
Any supplement
(n = 14,619)
No. of cases 878 143 252 1,619
Person-years 75,524 9134 16,815 109,173
Age-adjusted HR 1.00 (ref) 1.27 (1.07, 1.52) 1.10 (0.95, 1.26) 1.13 (1.04, 1.23)
Multivariable HR4 1.00 (ref) 1.25 (1.05, 1.50) 1.09 (0.94, 1.25) 1.10 (1.01, 1.20)
Excluding first 5 y5
No. of cases 464 76 131 822
Person-years 74,316 8938 16,448 106,793
Age-adjusted HR 1.00 (ref) 1.34 (1.05, 1.71) 1.12 (0.95, 1.36) 1.12 (0.99, 1.25)
Multivariable HR4 1.00 (ref) 1.32 (1.03, 1.68) 1.12 (0.92, 1.37) 1.08 (0.97, 1.22)
1 HR, hazard ratio (obtained from Cox proportional hazards models); ref, reference.
2 Vitamin C use not in combination with other supplements.
3 Multivitamin use not in combination with other supplements.
4 Adjusted for age (5-y age groups: 52, 53–57, 58–62, 63–67, 68–72, 73–77, or 78 y), waist circumference (,80 or 80 cm), smoking (never; mean
lifetime: 10 or .10 cigarettes/d), alcohol consumption (g/d in quartiles), steroid medication use (yes or no), educational level (,10, 10–12, or .12 y), and
hormone replacement therapy use (never, past, or current).
5 Risk of reversed causality checked by excluding the first 5 y of follow-up.