Relationship between intraocular pressure and obesity in Japan

Background Some cross-sectional studies have suggested that age, systolic b lood pressure and obesity are positively related to intraocular pressure (I OP), but few longitudinal studies have examined this relationship. This stu dy was carried out to evaluate the association between intraocular pressure and obesity by cross-sectional and longitudinal analyses in a large Japane se population. Methods Data were collected from annual health examinations between 1989 an d 1997 and reviewed retrospectively. Subjects of the cross-sectional analys is were 70 139 males and females aged 14-94 years. Among these subjects, 25 216 males and females who had undergone IOP measurements more than three t imes were analysed longitudinally. The association between IOP and obesity was examined cross-sectionally and longitudinally. Results Cross-sectional analysis: The mean IOP at the last visit was 11.6 m mHg. The IOP decreased gradually with age and was significantly higher in m ales than in females in almost all age groups. Body mass index (BMI) signif icantly correlated with IOP after controlling for age, gender and blood pre ssure. Longitudinal analysis: There was a significant association between l ongitudinal change in IOP and change in weight. This relationship remained significant after controlling for initial BMI, initial blood pressure, chan ge in blood pressure, gender and age. Conclusion This study showed a significant association between IOP and obes ity in both cross-sectional and longitudinal analysis. These findings sugge st that obesity is an independent risk factor for increase in IOP. Intraocu lar pressure, obesity, cross-sectional analysis, longitudinal analysis, blo od pressure, Japanese population.