Prevention of osteoporotic fractures: possibilities, the role of exercise, and limitations

The Effects of Combined Treatment with Naringin and Treadmill Exercise on Osteoporosis in Ovariectomized Rats

Osteoporosis is a disease characterized by low bone mass and progressive destruction of bone microstructure, resulting in increased the risk of fracture. Previous studies have demonstrated the effect of naringin (NG) or treadmill exercise (EX) on osteoporosis, however, reports about effects of NG plus EX on osteoporosis are limited. This study was designed to investigate the impact of combined treatment with naringin and treadmill exercise on osteoporosis in ovariectomized (OVX) rats. Three months after bilateral ovariectomy, Seventy-five rats were randomly assigned to the following treatment groups: OVX, sham-operated (SHAM), NG, EX, or NG plus EX treatment. Treatments were administered for 60 days. Bone metabolism, bone mineral density, trabecular bone parameters, immunohistochemistry, and the bone strength were evaluated. Compared to the OVX groups, all treatments increased bone volume (BV/TV), trabecula number (Tb.N), trabecula thickness (Tb.Th), bone mineral density (BMD), and mechanical strength. NG + EX showed the strongest effects on BV/TV, Tb.Th, and biomechanical strength. Additionally, decreased C-terminal telopeptides of type I collagen (CTX-1) and enhanced osteocalcin (OCN) expression were observed in the NG + EX group. The present study demonstrates that the NG + EX may have a therapeutic advantage over each monotherapy for the treatment of osteoporosis.

Predictors and Sequelae of Fractures in the Elderly: The Canadian Study of Health and Aging (CSHA)

The objective of this study was to describe the incidence, type, risk factors, and sequelae of fractures experienced by community-dwelling elderly Canadians. Data are from the Canadian Study of Health and Aging (CSHA), a longitudinal cohort study, collected in three waves: baseline (1991), wave 2 (1996), and wave 3 (2001). In CSHA-2 (1996), fractures were reported by 3.7 per cent of men and 7.5 per cent of women; in CSHA-3 (2001), by 2.9 per cent of men and 7.3 per cent of women. The distribution of fracture types was similar for men and women. Risk factors for women were increased age, history of fracture, and regular alcohol use; for men, stroke, arthritis, and lack of independent bathing. Walkers or wheelchairs were needed by over 30 per cent of those with any lower body fracture. One third of subjects with any fracture and over 50 per cent with femur fractures reported moderate or severe pain. It is concluded that elderly Canadians are at high risk for fractures, and older women are at most risk. Pain and mobility problems were common sequelae. The need for primary and secondary prevention of these age-related events is paramount.

Healthy aging as an intervention to minimize injury from falls among older people

With global trends toward population aging, many countries are adopting healthy aging policies to minimize disability and increase quality in the extended years of life. Falls in older people are a major contributor to functional decline generally associated with aging. Based on a study quantifying the relationship between healthy aging factors and risk of fall-related hip fracture in community-dwelling older people, this paper discusses evidence for the promotion of healthy aging as a population-based intervention for prevention of injuries from falls. To examine the protective effect of healthy aging on the risk of fall-related hip fractures, a case-control study was conducted with 387 participants. Persons aged 65 and over hospitalized with a fall-related hip fracture were matched with community-based controls recruited via electoral roll sampling. A questionnaire designed to assess lifestyle risk factors, identified as determinants of healthy aging, was administered during face-to-face interviews. After adjustment for health status and demographic factors, a number of lifestyle factors were seen to have a significant independent protective effect on the risk of hip fracture. These included never smoking, moderate alcohol consumption, being active, maintaining normal weight, and being proactive in preventive health care. Psychosocial factors included having supportive environments and personal resources to cope with stress. This study identified a range of modifiable lifestyle factors associated with fall-related hip fracture, suggesting that the "healthy aging" paradigm offers a comprehensive approach to falls injury prevention, and thus supports the adoption of healthy aging policies to extend years of quality life among older persons.

A low tension between individual and societal time aspects in health improved outcomes

OBJECTIVES

To review intertemporal choices, involving decisions with a trade-off between something now and something later. These choices are common in health both at an individual and societal level.

METHODS

The present value of an outcome, for example, the amount of money or the health outcomes in various aspects, is equivalent to the value of a future outcome discounted with the delay of time. The concept of diminishing value over time is positive discounting. Economic forecasts generally use discount rates in which the value of a future dollar is less than the value of a present dollar, and where the discount rates are similar for the individual investor and society. The value of future health is commonly thought of as similar to the value of future money. Yet, the individual may rationally choose a discount rate that is exceedingly low or even negative. This paradox is particularly relevant when considering primary and secondary prevention, where initial and continuing costs may precede beneficent outcomes by decades, making discount rate selections the dominant factor in determining decisions.

CONCLUSION

We suggest that the societal perspective should also recognize that discount rates for health outcomes are largely irrelevant and that even negative discount rates have crucial relevance.

Time-related issues with application to health gains and losses

Time-related aspects of health have attracted increasing interest, and it has become evident that many medical situations concern the exchange of present-day costs for future benefits. Traditional decision analytic paradigms weigh the probability of outcomes and the value of outcomes. Such analyses are incomplete if they do not consider the time of the outcome as well. The concept of diminishing value over time is positive discounting. Time discounting processes and effects have a potentially large impact on clinical decision making. Therefore, characteristics of discounting should be taken into consideration. Discounting processes are variable with individuals and also within different contexts such as gains and losses. No single model can be expected to describe time-related decisions within health. A more diversified use and critical appraisal of these concepts in medicine become more important as we attempt to refine decision models. A summary of valuation factors in medical decision making is presented: (a) long-term decisions are very sensitive to discount rates; (b) discount rates are greater for gains than for losses; (c) discount rates vary by domain, by outcome, by individuals over time, and by level of certainty; (d) individual preferences may reverse themselves over time; (e) the doctor uses expected value; the patient is risk aversive; (f) over a lifetime perspective, a flat or even negative discount rate will result in choices that minimize lifetime disability.

Results of conference questionnaire to participants on key issues in the prevention of osteoporosis

At a conference on recent progress in the prevention of osteoporosis a questionnaire on some key issues in prevention was distributed and replied to before the conference. Response rate was 63%. In general the expectations on the impacts of prevention were high. Life style changes were judged to be important, although somewhat weak scientific evidence. Cost effectiveness of preventive measures for osteoporosis were rated relatively high. More data on the place of oestrogen replacement therapy was needed for the oldest age-group, 75+ years. The attitude towards screening was positive. Respondents believed that hip fracture incidence would increase substantially in the world by the year 2020.