Introduction

The aging spine is subject to multiple onslaughts of metabolic slowdown, mechanical wear and tear, and immunological compromise. The process of aging is irreversible, but its detrimental fallout can partly be compensated by conditioning. Nutrition, weight control, and exercise are factors that can counter excessive decompensation of the aging spine.

Nutrition

Elderly populations are predisposed to malnutrition due to a variety of causes. The physiological changes associated with aging are altered glucose regulation and impaired hormonal homeostasis. There is decreased absorption of macronutrients (carbohydrates, proteins, and fatty acids) as well as micronutrients.¹ The decreased absorption of micronutrients in the elderly population is significant for cobalamin, calcium, vitamin D, riboflavin, and niacin.

Calcium absorption declines in both sexes in the elderly, and is directly related to vitamin D metabolism. Cobalamin (vitamin B₁₂) absorption decreases in the elderly and predisposes them to subacute combined degeneration of the spinal cord.² Other vitamin B complexes may also have malabsorption, leading to neuropathies. The elderly have consistently lower levels of vitamin D. In a European study, vitamin D levels are lowest in winter in the elderly.³ This tendency of decreased sun exposure and decreased capacity of the aging kidney to convert vitamin D to active form may reduce endogenous levels of vitamin D. Western diets only supply 25% to 50% of the vitamin D daily requirement; hence, supplementation in the elderly is crucial.

Other coexisting conditions in the elderly can also cause imbalances in nutrition. Extensive use of antibiotics can cause cobalamin deficiency. Other disorders such as Alzheimer disease may cause the patient to forget about having a meal. Parkinson disease and other movement disorders may prevent patients from feeding themselves adequately. Diabetes, hypertension, and other chronic conditions may directly, or indirectly, through the drugs used for treatment, cause anorexia in the elderly.

Anorexia and decreased food intake is prevalent in the elderly population.⁴ Other than the previously noted causes of anorexia, elderly patients also suffer from psychological anorexia. It may originate from various life events such as loneliness, death of a spouse, lack of social life, estrangement from family, and loss of independence. It is important to recognize these major life events and provide the elderly population with counseling and support. Anorexia may also originate from the natural process of aging and changes within the central nervous centers for feeding and hydration. Although this change is inevitable and irreversible, it should not necessarily lead to undernourishment but merely readjust the food intake to the new levels. However, due to the complex interactions of aging, coexisting conditions, and life events occurring around aging, it may lead to malnutrition if not monitored.

The often neglected facet of malnutrition in the elderly population is the socioeconomic conditions that may hinder intake of well-balanced foods. Physicians and healthcare workers fail to take into account that most elderly people are not in control of their food intake. They may live at chronic care homes and group homes; thus they may only have access to standardized diets and have difficulty changing their diet to meet their specific health needs. Also, the elderly may not have a source of income to afford the diet or the dietary supplements we may recommend.

The elderly population is thus nutritionally vulnerable to deficiencies due to a combination of biological, social, and psychological causes. The nutritional deficiencies can affect various parts of the aging spine. Calcium and vitamin D imbalance affecting the vertebral column, vitamin B complexes such as B6 affecting the peripheral nerve conduction, decreased proteins causing paraspinal muscle atrophy, and vitamin B complex deficiency causing dorsal column symptoms illustrate a few examples. Thus it is important to anticipate these problems and actively monitor nutritional status in the elderly and supplement with easily available and affordable alternatives.