Estimating geriatric patient's body weight using the knee height caliper and mid-arm circumference in Hong Kong Chinese.

The use of the knee height caliper is a convenient way to estimate a patient's body weight. However, the equation devised to estimate an individual's body weight was specifically designed for Caucasians and Blacks. Therefore, this study is to assess the suitability of the knee height caliper among Chinese geriatric patients residing in Hong Kong. Over a six-month period, all geriatric patients from an acute care hospital and private nursing home in the Kwun Tong were recruited into the study. Only patients/residents that were considered unstable with ascites; low blood pressure; on cardiac monitors or had respiratory difficulties were excluded. Measurements from the knee height caliper and mid-arm muscle circumference of the patients were necessary for estimating their body weights. The actual body weights measured with calibrated bed, chair or portable scales was compared with the calculated body weights from the equation. A comparison of the mean and linear regression was performed for analysis of the results. A total of 300 geriatric patients (200 females and 100 males) were recruited. The mean MAC and knee height results were as follows: 25.1 cm (SD 3.9) for females and 26.2 cm (SD 3.2) for males; and 45.75 cm (SD 2.09) for females and 48.98 cm (SD 2.09) for males respectively. The mean difference among the male group was 0.4222 (95% CI: -0.54, 1.39) with a mean estimated body weight of 58.1 kg (SD 10.1) and a mean actual body weight of 57.7 kg (SD 9.9). The mean difference among the female group was 2.9649 (95% CI: 2.30, 3.63) with a mean estimated body weight of 51.6 kg (SD 10.9) and a mean actual body weight of 48.6 kg (SD 10.1). A new equation devised from the data is as follows: Chinese males (over 60 years of age) (R-square -0.81) Weight = [knee height (cm) x 0.928 + mid-arm circumference (cm) x 2.508 - age (years) x 0.144] - 42.543 +/-9.9kg of actual weight for 95% of Chinese males; Chinese females (over 60 years of age) (R-square - 0.82) Weight (kg) = [knee height (cm) x 0.826 + mid-arm circumference (cm) x 2.116 - age (years) x 0.133] - 31.486 +/-10.1kg of actual weight for 95% of Chinese females. The results showed that the mean estimated body weight calculated from the knee height equation (for Caucasians) was significantly larger than the mean actual body weight for the Chinese subjects. This study suggests that the knee height caliper is a useful tool for estimating the body weights. However, a multi-center study is necessary to validate the new equation for the elderly Chinese population.

Depletion of linoleate induced by weight cycling is independent of extent of calorie restriction.

Recent epidemiological studies have suggested that weight cycling induced by repeated dieting over time may increase the risk of cardiovascular disease. It is speculated that the increased mortality from coronary heart disease for people with a history of excessive weight cycling could be attributed to change in lipid metabolism. Previous studies have demonstrated that repeated cycling of 100% food restriction followed by ad libitum refeeding caused a depletion of linoleate and alpha-linolenate in rats. The objective of the present study was to test the hypothesis that the weight cycling-induced reduction in linoleate and alpha-linolenate is independent of extent of calorie restriction. Two consecutive weight cycles in three experiments were induced by 100% calorie restriction, 60% calorie restriction, and 36% calorie restriction, respectively, followed by ad libitum refeeding. As the consequence of the two weight cycles, linoleate and linolenate were decreased, whereas myristate, palmitate, and palmitoleate were proportionally increased in carcass and adipose tissue lipids. The results of all three experiments showed a preferential depletion of linoleate and alpha-linolenate without changes in final body weight, total body fat, and adipose tissue pads in the weight-cycled rats. In addition, the triacylglycerol species profile in the adipose tissue of weight-cycled rats was significantly remodeled, with a proportional depletion of linoleate-enriched triacylglycerol species (LLL, LLO, and LLP, where L, O, and P are linoleic, oleic, and palmitic acid, respectively) and a proportional accumulation of palmitate-enriched triacylglycerol species (OPPo, PPPo, and PPP, where Po is palmitoleic acid). We conclude that weight cycling changes the ratio of polyunsaturated fatty acids to saturated fatty acids and remodels the adipose tissue triacylglycerol species profile in rats.