A two year follow-up of a hypertension screening programme Napier 1973-1975

Two years after a hypertension screening survey conducted at Napier in 1973 the blood pressure levels of 350 adults were re-examined. The sample comprised 152 persons previously referred for investigation because of high blood pressure detected during the 1973 survey, a matched control group of 146 normotensives and a small supplementary control group. Of the 152 persons in the referred group 31 (20.4%) were under medical supervision at the time of the 1973 survey, 89 (58.5%) attended a doctor within the next 12 months and 32 (21.1%) took no further action. Two years later the 31 cases previously under medical supervision had remained on therapy but only 43 of the 89 new cases were receiving treatment at the time of re-examination. More than 50% of the cases in the referred group showed a decrease in the mean systolic pressure of 10mmHg or greater over the two-year period compared with 20.5% of the normotensive control group. Only 32% of referred cases were regarded as effectively controlled at the time of re-examination ie had mean systolic pressures less than 160mmHg and mean diastolic pressures less than 95mmHg. The low level of effective control resulting from the earlier survey casts further doubt on the value of mass screening procedures for hypertension.