The skin has many functions including physical and immunological protection, fluid balance, temperature regulation, vitamin D production and visual signalling.
Skin problems are the commonest reason for GP consultation after pain, yet the last unselected population study in the UK was in 1976. This was a community survey of skin disease carried out in Lambeth, London. In this study, the most common skin condition in the oldest participants was eczema. Of those with a skin disease thought to justify medical care, only 21% reported having attended their GP in the past six months for a skin complaint.1
There are physical changes to the skin as we age such as wrinkles, sagging, thin skin (except soles of feet), loss of elasticity, pigmentary changes, dryness and loss of luminosity. Skin problems include lesions, pruritus, rashes (such as eczemas, psoriasis, drug eruptions, blistering), leg ulcers, stasis disease, red legs, infections and infestations.
Itching is a frequent problem. Many cohort studies have contributed data and it is quoted as the commonest skin complaint in elderly people.2 Prevalence increases with advancing age and it is slightly more common in women and in winter.3
Since the end of the 20th century, evidence has accrued that there are itch-specific sensory neurones in skin.4,5 Specialised neurones for histamine-induced itch are anatomically identical to pain fibres but functionally different. Some itch is carried by less specific pain fibres. C fibre bundles (including the nociceptors) deteriorate with age which may lead to spontaneous activity. Could this be the mechanism in “senile pruritus”?
There are many types of itch from pruritoceptive (skin disease) and neuropathic itch (damage or malfunction of nerves) to neurogenic (no visible pathology) and psychogenic itch. Pruritus may have developed in evolutionary terms from the need to rid the skin of parasites. Although scabies is a common cause of itching in elderly in UK care homes, most people who itch do not have parasitic diseases.
Systemic causes of itching can include iron deficiency, liver dysfunction (cholestasis), renal disease (chronic), blood dyscrasias (polycythaemia), thyroid dysfunction, cerebrovascular, malignancy, HIV or drugs.
Drug-induced itch is sometimes not associated with a visible rash but mostly itch without a rash is associated with dry skin. Older skin can be dryer due to altered water and lipid content and deterioration of the stratum corneum, which then forms a poor barrier. There is also reduced sebum and sweat production as well as external influences such as excessive washing, detergents and soaps, pH and low humidity. A management plan would be to treat any relevant condition, explain itch-scratch cycle, keep fingernails short, increase humidity, explain choice of fabrics next to skin and ask patients to avoid hot baths and irritants (including talcum powder) while supplying adequate amounts of emollients and soap substitutes.
Skin problems can be dangerous and certainly impact on quality of life yet skin care is considered to be “personal care” rather than medical care and skilled help with topical therapy is not always available. In addition, nurse education does not always include any practical dermatology training.
1. Rea JN, et al. British Journal of Preventative and Social Medicine 1976; 30: 107-14
2. Ward JR, et al. Int J Dermatol 2005; 44: 267–73
3. Weisshaar E and Greaves MW in Evidence Based Dermatology 2nd edition 2008 Blackwell Publishing, London
4. Schmelz M, et al. J Neuroscience 1997; 17: 8003-8
5. Schmelz M. Neursci and Biobehav Rev; 2009