Osteoporosis, vertebral fractures and mortality in a Japanese rural community

Abstract

Objectives: The present study aims to determine the relationship between osteoporosis (OP), vertebral fracture (VF) and mortality.

Methods: We followed up 1024 residents of Miyagawa village every 2 years for a mean of 8.4 years between 1997 and 2009. The residents were assessed every 2 years. We defined OP as T scores for bone mineral density that were < 2.5 standard deviations below peak bone mass. VF was assessed by lateral radiography of the thoracic and lumbar spine. The participants were allocated as follows depending on the presence or absence of OP and VF: with OP and without VF (OP group), with VF and without OP (VF group), with OP and VF (OP + VF group) and without OP and VF (Control group). We determined survival/mortality rates until 2011 by reviewing medical histories and death certificates.

Results: By 2011, 304 participants had died. The respective 5-year survival rates for the OP + VF, OP, VF and Control groups were 80.6%, 93.7%, 87.8% and 94.2%. Mortality rates were significantly worse for the OP + VF group than the Control group (OP + VF Hazard Ratio: 1.89; 95% CI, 1.27-2.77).

Conclusion: Prevention of osteoporotic VF in elderly persons is very important from the viewpoint of increasing life expectancy.

Keywords: Elderly; Epidemiology; Mortality; Osteoporosis; Vertebral fractures.