Increased Parkinson’s risk seen for women with low BMD in new study
In postmenopausal women, osteoporosis found to be key risk factor
Osteoporosis, a condition marked by fragile bones and very low bone mineral density (BMD), was associated with an increased risk of Parkinson’s disease in postmenopausal women, a new large-scale study in Korea found.
In fact, “individuals with osteoporosis had a 1.40-fold higher HR [hazard ratio] … than those with a normal BMD,” the researchers wrote. A hazard ratio is the probability of an event occurring in a study group relative to the control group over a period of time.
Data indicated that using medications to treat osteoporosis in women after the onset of menopause — when menstrual cycles have stopped for at least one year — markedly reduced this elevated risk.
“Proper management of BMD in postmenopausal women may help prevent [Parkinson’s disease],” the team wrote.
Their study, “Bone Mineral Density and the Risk of Parkinson’s Disease in Postmenopausal Women,” was published in the journal Movement Disorders.
All women in this study of postmenopausal osteoporosis are age 66
Emerging evidence suggests people with Parkinson’s disease have an increased risk of bone fractures and osteoporosis, a condition characterized by severe low bone mass and deterioration of bone tissue. Conversely, using medications to treat osteoporosis has been shown to have a neuroprotective effect.
Importantly, the risk of osteoporosis has been seen to increase as people age — and research has shown that women may lose bone mass more rapidly following the onset of menopause.
Now, researchers in South Korea sought to determine whether bone mass density or BMD, a measure of bone health, is related to the risk of Parkinson’s disease in postmenopausal women. Postmenopause is a term often used to describe the time after menopause’s onset.
Data were collected from the National Health Insurance Service (NHIS) in South Korea, a universal health insurance system covering most of the Korean population. BMD was assessed using dual-energy X-ray absorptiometry (DXA) of the lower (lumbar) spine.
The study included 272,604 women, all age 66. Among them, nearly 4 of every 10 — 104,242 or 38.2% — had osteoporosis, while 116,371 (42.7%) had osteopenia, a less severe form of low BMD that can lead to osteoporosis. Within one year of the study’s start (baseline), 27.8% had used osteoporosis medications, while 76.2% received these medications during follow-up.
Over a median follow-up of 7.7 years, 2,884 (1.1%) women were diagnosed with Parkinson’s disease.
The results revealed no significant difference in the incidence of Parkinson’s between the osteopenia group compared with the normal BMD group.
However, osteoporosis was significantly associated with a 22% relative increased risk of Parkinson’s after adjusting for influencing factors. Such factors included smoking status, alcohol consumption, physical activity, income, obesity, high blood pressure, type 2 diabetes, high blood fats, called dyslipidemia, and chronic kidney disease.
Further adjustments for the use of osteoporosis medications led to a 40% increased Parkinson’s risk with osteoporosis.
Greater risk of Parkinson’s found for women who do not smoke
Subgroup analysis found non-smokers with osteoporosis had a higher risk of Parkinson’s than those with a normal BMD. However, no similarly greater risk was found women who did smoke.
“Osteoporosis did not significantly increase the risk of [Parkinson’s] in women who were current smokers,” the researchers wrote.
The risk of Parkinson’s was higher in patients without a history of osteoporosis medications compared with those who had used these therapies within one year of baseline and during follow-up.
Among individuals without a history of osteoporosis medications, the risk of Parkinson’s was higher in patients with osteopenia, with an increase of 16%, and osteoporosis — a 60% increase — at baseline.
Still, this risk was reduced, or attenuated, in those who had used osteoporosis treatments during follow-up, as well as those with continuous use before and after enrollment in the study. At five years, the risk of Parkinson’s dropped by 38% with the use of osteoporosis medications compared with no such treatment.
“Lower BMD was associated with an incident [Parkinson’s disease] in postmenopausal women, and individuals with osteoporosis had a significantly higher risk of [Parkinson’s disease] than those with a normal BMD,” the team concluded, noting further that “this association between BMD and [Parkinson’s disease] risk was prominent in those without a history of [osteoporosis medication] use.”