Our study of more than 2,500 GPs from 29 countries found about 60% of GPs reported use of guidelines when treating hypertension in frail oldest-old. These proportions varied largely between countries, from less than 25% in New Zealand to almost 90% in Ukraine. Less experienced GPs and female GPs were more likely to use guidelines. However, GPs from all countries overall made similar treatment decisions when confronted with cases of frail oldest-old patients, whether or not they used guidelines, and regardless which guidelines they used.
Clinical context and comparison with existing literature
While guideline use seems to have little or no effect on treatment decisions in frail oldest-old, frailty, systolic blood pressure and history of cardiovascular disease have [11]. In addition, country-specific factors such as cardiovascular burden and life expectancy are associated with the decisions when managing hypertension in this age group [12].
An explanation why guideline use is not associated with treatment decisions could be the absence of specific and clear recommendations in most current guidelines for this population group, since in the majority of hypertension trials frail and oldest-old patients are excluded [15]. Therefore GPs are left to decide based on other factors such as patient characteristics rather than on guidelines [16]. We speculate GPs would use more guidelines if they were more applicable to the types of patients they treat. Moreover, the literature outlines patient safety to be more important than adherence to guidelines [17].
Some guidelines, however, provide specific recommendations for the oldest-old e.g. the NHG guideline about cardiovascular disease risk management implemented in the Netherlands [18]. This work was an initiative of Dutch GPs involving all healthcare professionals in cardiovascular disease prevention in a multidisciplinary workgroup. The 2012 version, which was applied at the time of the survey, was recently updated in spring 2019 and now also contains specific recommendations for frail patients. In our study, in the case of primary prevention and SBP of 160mmHg, we could see that NHG-users seemed to treat less, however, the confidence interval overlapped with the proportions of GPs that adhered to other or no guidelines. This observation may imply that guidelines could influence GPs’ treatments decision in frail oldest-old if specific recommendations are provided.
In the present study we found that female doctors were more likely to use hypertension guidelines when treating frail oldest-old patients. This is in line with findings from other studies that described higher adherence to clinical guidelines by female physicians when treating other chronic conditions such as diabetes [19].
Limitations and strengths
This study has several limitations but also strengths: Asking GPs what they would do is not the same as measuring what they actually do. However, the use of a case-vignette study allows comparing decisions in different countries while still having a standardized situation which can be seen as a strength when comparing across countries. We believe anonymity also lowered social desirability bias risk. Studies including GPs often have a moderate response rate. Our median response rate of 26% is not uncommon, but we, like others, must take the risk of selection bias into account. We mitigated that risk by running a sensitivity analysis of countries where the response rate was higher (more than 60%). We further acknowledge that due to different numbers of participants per country the list of most used guidelines is skewed to overestimate responses from countries with many participants. However, we focused on the variety by including almost 30 countries, some being able to recruit more, some to recruit less GPs. This approach also let us include response from countries sometimes under-represented in research. Moreover it is the first study to our knowledge to investigate guideline use and treatment decisions in frail and oldest-old with hypertension through standardized case vignettes.
Implications for research and/or practice
Until future trials in primary care with oldest-old and frail patients will assess the benefit as well as risks of hypertension treatment in this population group, our study suggests that due to the remaining clinical dilemma, some GPs will choose not to follow any guidelines. One explanation may be the absence of specific recommendations for this heterogenous group of oldest-old patients. The development of future guidelines should ideally help in achieving a higher agreement among guidelines. The absence of agreement between the various recommendations was found to be associated with a large variation in how GPs apply preventive measures [20]. Further, guideline committees would benefit from larger efforts in consulting patients as well as GPs to raise more awareness of their patients’ specificity. This would decrease the potential of conflicting interests compared to guidelines written by professional societies and might lower the risk of overtreatment [21,22]. The actual format of guidelines with an often complex and ambiguous text can be a barrier to GPs adoption of recommendations [23].