[Mammographic screening does not reduce breast cancer mortality]

The outcome of a Swedish mammographic screening programme has been studied by analysis of official health statistics for 1987-96. The study series comprised 605,260 women (70 per cent of those aged 50-69 years at inclusion in the mammography programme), representing 4,908,176 woman-years, 1,932,353 mammographies, and 6,713 deaths due to breast cancer. The observed number of deaths was 55 (0.8%) less than would have been expected had the screening not been performed (ns), whereas findings in the Two County Council study suggest that the reduction in mortality should have been 28 per cent (n = 739) for the group and period studied. Thus, the cost of saving a single life was estimated to have been SEK 18-25 million (approximately GBP 1.3(1.8 m. USD 2.36(3.17 m).

Factors affecting the validity of the standard blood pressure cuff

Fifty-eight patients, 31 women and 27 men, with a wide range of upper arm circumferences (20-43 cm), ages (16-82 years) and body mass indices (16-55 kg m-2) were studied. The direct blood pressure was measured in the brachial artery in one arm and simultaneously the indirect pressure was measured in the other arm using a large standard cuff (rubber bag 12 x 35 cm). The mean intra-arterial blood pressure was (systolic/diastolic) 137 +/- 25 mmHg (SD)/76 +/- 10 mmHg. With the cuff the mean blood pressure was 134 +/- 23 mmHg/85 +/- 11 mmHg. The cuff significantly underestimated the systolic blood pressure (3.2 +/- 11.4 mmHg, range -25-30 mmHg) while the diastolic pressure was overestimated significantly (8.8 +/- 8.5 mmHg, range -32-14 mmHg). The direct/indirect blood pressure difference correlated significantly to the intra-arterial systolic and diastolic pressures (systolic/diastolic; r = 0.44, P = 0.0006/r = 0.36, P = 0.0062), but only to the auscultatory diastolic pressure (r = -0.02, P = 0.9/r = -0.45, P = 0.0004). The direct/indirect difference correlated significantly to the arm circumference (r = -0.33, P = 0.01/r = -0.30, P = 0.02) as did the diastolic direct/indirect difference to pulse rate (r = 0.34, P = 0.009). Age did not correlate significantly to the direct/indirect blood pressure difference in this study (r = -0.02, P = 0.9/r = -0.10, P = 0.5). It can be concluded that in addition to the ratio between the arm circumference and the width of the cuff (rubber bag), there are other sources of systematic errors of indirect blood pressure measurement, in particular pulse rate and the level of indirect blood pressure. If corrections could be made with regard to these variables, it is obvious that the reliability of the indirect method, especially when used in epidemiological contexts, would increase.

Improved accuracy of indirect blood pressure measurement in patients with obese arms

We studied 20 patients with moderate to severe obesity (body mass index 37 +/- 8 kg/m2) with obese arms (arm circumference 37 +/- 4 cm). Their blood pressure was measured directly in the brachial artery in one arm and simultaneously indirectly in the other arm using either a large standard cuff (rubber bag 12 x 35 cm) or a new cuff (the Tricuff, Pressure Group AB, Stockholm) containing three rubber bags of different sizes, which automatically selected the appropriately sized bag in relation to arm circumference. Both cuffs showed a significant overestimation of the diastolic blood pressure (standard cuff 13 mm Hg, P < .001, Tricuff 6 mm Hg, P < .01). The error of the standard cuff was significantly greater than that of the Tricuff (P < .001). The differences in systolic blood pressure between the intraarterially and the indirectly measured results were small (0.2 to 3 mm Hg) and not statistically significant with either cuff. The new Tricuff offered an advantage as compared to a large standard cuff in terms of a lesser overestimation of the diastolic blood pressure. In practical terms, this should lead to a reduction in the overestimation of diastolic hypertension in obese individuals.

Is blood pressure measurement with a standard cuff reliable?

This study compares blood pressures measured with a standard cuff (rubber bag 12 x 35 cm) with concomitantly measured intra-arterial pressures in 48 subjects. With the standard cuff, and using a diagnostic cut-off limit for diastolic hypertension of 90 mmHg, 15/48 patients were found to be hypertensive, whereas only 4/48 had intraarterial pressure above 90 mmHg. Thus, the specificity of the non-invasive method was only 75%. If higher diagnostic cut-off limits were used, e.g. 95 mmHg, specificity increased to 84%, and with lower cut-offs specificity was 63% for 85 mmHg and 52% for 80 mmHg. A specificity of only 75% is very poor for a method commonly used in screening examinations and may lead to considerable over-diagnosis of mild hypertension.

The reliability of auscultatory measurement of arterial blood pressure. A comparison of the standard and a new methodology

In 48 individuals with a wide range of arm circumferences blood pressure measured indirectly with two different cuffs was compared to direct intraarterial measurements. The two cuffs were a standard size cuff (12 X 35 cm) and a newly developed cuff, containing three rubber bags of different sizes, which automatically selects the appropriately sized bag in relation to arm circumference (Tricuff, Pressure Group AB, Sweden). The Tricuff correctly placed 42 of the 43 patients in the "normotensive" range, ie, diastolic blood pressure less than 90 mm Hg, whereas the standard cuff put only 33 of 44 patients in this range (P less than .005). The discrepancy was not only due to the expected better performance in patients with obese arms, but also in the subgroup of patients with arms in the range 22 to 31 cm, in which group both cuffs would measure blood pressure with a 12 cm wide rubber bag. The number of correctly identified "normotensive" patients was noticeably higher with the Tricuff than with the standard cuff (30/31 v 25/32, P = .053). The better specificity of the new cuff thus offers an improvement over the standard cuff. There are several potential clinical advantages of this, mainly that the risk of erroneously labelling normotensive individuals as hypertensive is reduced.

The impact of new technologies in primary health care

This article surveys the gradual diffusion of diagnostic technologies into homes in Sweden. The author speculates on the advantages and prospective problems of home care. In addition, the article proposes some general guides to assure that new technologies provide genuine benefits for the patient.

Effect of establishing a primary health care centre on the utilization of primary health care and other out-patient care in a Swedish urban area

The aim of the study was to describe the changes in the way the population in the catchment area of one parish in Stockholm utilized the available out-patient services after primary health care in the area had been expanded by establishing the Matteus health centre. Primary health care resources in the district expanded from two district physicians, one assistant physician and four district nurses before the project started to 7.5 district physicians, 15 district nurses plus other assistant personnel. A controlled longitudinal before and after design was used over a period of four years, 1978-81. The results showed that the population in the study district doubled the number of visits to district physicians and nurses after establishment of the health centre. Visits to hospital out-patient clinics were reduced by 26% (40% reduction for emergency visits and 16% for polyclinic appointments). Visits to nonpublic employed physicians (private, occupational and school health physicians) decreased by 31% after establishment of the Matteus health centre. Furthermore the population decreased their utilization of the Stockholm emergency car service by 28%. These results support the workload reduction hypothesis--that an expansion of primary health care leads to a reduction of the workload of hospitals, and not an overall increase in utilization of health care.

Relationship between use of increased primary health care and other out-patient care in a Swedish urban area. IV. Use of private and other non public out-patient care

In 1979 Stockholm County Council began a study of increased primary health care (PHC) at Matteus Primary Health Care Centre (MPHCC) in Stockolm city. The aims were to analyse changes in utilization of out-patient care (OPC). This article analyses the changes in the population's visits to non-public employed physicians. The study has a longitudinal design and covers a study and two control districts. The method is an enquiry before and after establishment of the MPHCC in the northern part of Stockholm city. In this study it was shown that increased PHC in the study district resulted in a significant decrease (27%) of the population's visits to private-, occupational- and school health physicians. Furthermore, the study shows a significant decrease of the number of individuals in the study district who visit these non-public employed physicians during a 12-month-period.

Relationship between use of increased primary health care service and other care in a Swedish urban area. III. Utilization of emergency house calls

The Matteus Primary Health Care Centre (MPHCC) is a pilot project with fullscale established future primary health care. Before the project began, the average district of a general practitioner consisted of 9 000 inhabitants. After the start of MPHCC the district level was 3 000 inhabitants per general practitioner in the study district. The populations utilization of the Stockholm emergency car service (SCS) has been analysed both before and after the establishing of the MPHCC in the northern inner city of Stockholm. The results confirm the hypotheses that the establishment of MPHCC reduces the workload on the SCS by 24%. The reduction is significant in all ages and for both men and women. The main period of the reduction is on weekdays 7 a.m. to 5 p.m. when the MPHCC is open.

Relationship between use of increased primary health care and other out-patient care in a Swedish urban area. II. Utilisation of out-patient hospital services

The expansion of the primary care services and its effect on utilization of the out-patient services in hospitals by the public have been analysed by a number of authors. Evaluation of the links vary: some studies state that an expansion of primary care goes together with an increase or an unchanged utilization of hospital visits - out-patient clinics, while others say that a decrease occurs. The present study analyses this problem in Stockholm city. This study has a longitudinal design and it covers a study district and a control district. The results support the hypothesis that the expansion of primary care in the study area results in a significant decrease in hospital visits in this area. The decrease occurred in most age groups among men as well as women, regardless of the type of visit (emergency or by appointment); it also occurred in the usual speciality areas in the general practitioner's everyday work.

Relationship between use of increased primary health care and other out-patient care in a Swedish urban area. I. Utilisation of public primary health care

The Swedish National Health and Medical Care program is currently undergoing a change. The aim of this gradual change is a more decentralized system where the primary care service is expanded to cater for the transfer of patients from the hospitals over to primary care. This study, which is one part of a longitudinal design aims to show changes in public utilization of the services of general practitioners and district nurses after the expansion of the Matteus Primary Health Care Centre (MPHCC), city of Stockholm. The analysis is based partly on the annual statistical records and partly on medical chart studies of visits to the general practitioner by a selected population. The results showed that the population in the study district made twice as many visits to general practitioners and district nurses after the establishment of the MPHCC. It was also shown that the number of individuals visiting the general practitioners more than doubled during an 18-month period following the expansion of MPHCC. These results corresponds well with the aims associated with the expansion in primary care in future medical care services.