Incidence of hay fever in a North London practice.

A practice in North west London consisting of about 6,000 patients, 30 per cent of whom are immigrant, yielded a sample of 77 patients who could be considered to be suffering from hay fever. These were questioned and skin tested.The disease was found to be more prevalent in the immigrant West Indian section of the practice. These patients had not suffered from the disease before arrival in this country but had developed their symptoms after an interval of up to 14 years with an average of about five years. Most of the patients had arrived in this country as adults, and some differences in the pattern of disease from that encountered in the indigenous population were observed. The tendency is for the disease to begin between the age of five and 15 for the indigenous patient, although extreme cases with ages of onset of two and 74 years were found. However, in the immigrant West Indian group the age of onset tended to be between 25 and 45. In addition, the older an immigrant was on arrival in this country the longer hay fever took to develop. It was found that May was stated to be the month of onset of the disease for the indigenous group whereas June tended to be the month of onset for the immigrant group.The sample proved too small to detect any existing patterns in personal or family history, but sex links were found in both response to grass pollen and a personal history of asthma, in that men showed less tendency to asthma whilst proportionately less women than men responded to grass pollen skin tests only.We suggest that a diagnosis of hay fever should be considered in both the young and the elderly who present with recurrent symptoms occurring only in the summer months, of one or more of the following: sneezing, lacrimation, nasal drip, nasal blockage, wheezing, dry throat, or itchy eyes. The diagnosis can readily be confirmed by simple skin testing.