Reason for discontinuation of newly prescribed antihypertensive medications: methods of a pilot study using computerized patient records

Abstract

Objective—The purpose of this pilot study was to examine the feasibility of using computerized medical records retrospectively to identify patients and their physicians for subsequent survey to examine discontinuation of a newly prescribed antihypertensive medication in primary care, while maintaining patient confidentiality. Design—A case – control study utilizing UKPCD (formerly MediPlus®), a large automated database of computerized medical records, and direct collection of information from patients and their physicians. Setting—Eight selected general practices in the United Kingdom. Participants—Thirty‐two patients, identified with a newly prescribed antihypertensive (index) medication and classified by their treatment status (discontinuer vs continuer) and five physicians were surveyed. Results—The participation rate was low among physicians (19%), likely to be due to recruitment during the holiday season, but higher among eligible patients (70%). A higher proportion of discontinuers (37%) refused or failed to respond to the invitation to participate compared with continuers (27%). For most patients, self‐reported treatment status matched the UKPCD‐based classification of discontinuer or continuer (kappa = 0.67); agreement of UKPCD data with physicians was moderate (kappa = 0.53). The extent and accuracy of the information collected from patients demonstrated that they were able and willing to report detailed knowledge of their medications and recent symptoms. Discontinuers, however, had difficulty recalling the discontinued medication on their own, possibly due to the amount of time elapsed between the event and the questionnaire administration. Conclusion—This pilot study demonstrates the feasibility of examining medication discontinuation in an ambulatory setting by utilizing a large automated database of computerized records to identify and recruit eligible physicians and their hypertensive patients for study, while maintaining patient and physician privacy. Modifications to the methodology to increase physician and patient participation and recall, and to decrease the time between the index event and patient query would increase its utility in larger studies. Copyright © 2000 John Wiley & Sons, Ltd.

A review of studies of adherence with antihypertensive drugs using prescription databases

“…A Japanese questionnaire-based study found 49% of patients with well controlled blood pressure reporting adverse effects with their antihypertensive medicines and a statistically significant relationship between the number of reported adverse effects and nonadherence (Toyoshima et al 1997). However, it has been observed elsewhere that patients who discontinue are less likely to respond to questionnaires (Suarez et al 2000), so that the results of this study should be interpreted with caution. Certainly it is known that polypharmacy increases the risk of adverse effects due to drug interactions.…”

“…The length of this period ranged from 3 to 12 months; however, there was usually no attempt to justify this choice. A study based on the UK General Practice Research Database (UKGPRD) concluded that a 4-month period without prescriptions was not sufficiently long to identify new users of antihypertensive drugs and that a 12-month period would be more appropriate (Suarez et al 2000). This finding is not necessarily applicable to other databases, but it is possible that the studies choosing relatively short run-in periods may include a substantial number of patients who are not new to antihypertensive therapy.…”

“…There were no attempts to validate the choice of duration of the period without therapy. Suarez et al (2000), in their study of the UKGPRD, found that 4 months was an insufficient period for identification of new users of antihypertensive therapies; that is, they found that there were a large number of patients who, although failing to collect their prescriptions for 4 months, returned to some form of antihypertensive therapy. If this finding holds true for other populations, it appears that many discontinuations may be more properly regarded as breaks in therapy.…”

A review of studies of adherence with antihypertensive drugs using prescription databases

“…A Japanese questionnaire-based study found 49% of patients with well controlled blood pressure reporting adverse effects with their antihypertensive medicines and a statistically significant relationship between the number of reported adverse effects and nonadherence (Toyoshima et al 1997). However, it has been observed elsewhere that patients who discontinue are less likely to respond to questionnaires (Suarez et al 2000), so that the results of this study should be interpreted with caution. Certainly it is known that polypharmacy increases the risk of adverse effects due to drug interactions.…”

“…The length of this period ranged from 3 to 12 months; however, there was usually no attempt to justify this choice. A study based on the UK General Practice Research Database (UKGPRD) concluded that a 4-month period without prescriptions was not sufficiently long to identify new users of antihypertensive drugs and that a 12-month period would be more appropriate (Suarez et al 2000). This finding is not necessarily applicable to other databases, but it is possible that the studies choosing relatively short run-in periods may include a substantial number of patients who are not new to antihypertensive therapy.…”

“…There were no attempts to validate the choice of duration of the period without therapy. Suarez et al (2000), in their study of the UKGPRD, found that 4 months was an insufficient period for identification of new users of antihypertensive therapies; that is, they found that there were a large number of patients who, although failing to collect their prescriptions for 4 months, returned to some form of antihypertensive therapy. If this finding holds true for other populations, it appears that many discontinuations may be more properly regarded as breaks in therapy.…”

Systematic review of scope and quality of electronic patient record data in primary care

“…One study used video recording of the consultation to evaluate the EPR content compared with the use of notes and UK national statistics (fourth national study of morbidity in general practice, MSGP4) for comparative measures 18. Seven studies carried out questionnaire and telephone surveying for a reference standard with data gathered from the patient, carer, or both 13 14 19 20 22 – 24. These studies involved the sampling of a study population from the database for subsequent validation through questionnaires.…”

A review of studies of adherence with antihypertensive drugs using prescription databases

“…A Japanese questionnaire-based study found 49% of patients with well controlled blood pressure reporting adverse effects with their antihypertensive medicines and a statistically significant relationship between the number of reported adverse effects and nonadherence (Toyoshima et al 1997). However, it has been observed elsewhere that patients who discontinue are less likely to respond to questionnaires (Suarez et al 2000), so that the results of this study should be interpreted with caution. Certainly it is known that polypharmacy increases the risk of adverse effects due to drug interactions.…”

“…The length of this period ranged from 3 to 12 months; however, there was usually no attempt to justify this choice. A study based on the UK General Practice Research Database (UKGPRD) concluded that a 4-month period without prescriptions was not sufficiently long to identify new users of antihypertensive drugs and that a 12-month period would be more appropriate (Suarez et al 2000). This finding is not necessarily applicable to other databases, but it is possible that the studies choosing relatively short run-in periods may include a substantial number of patients who are not new to antihypertensive therapy.…”

“…There were no attempts to validate the choice of duration of the period without therapy. Suarez et al (2000), in their study of the UKGPRD, found that 4 months was an insufficient period for identification of new users of antihypertensive therapies; that is, they found that there were a large number of patients who, although failing to collect their prescriptions for 4 months, returned to some form of antihypertensive therapy. If this finding holds true for other populations, it appears that many discontinuations may be more properly regarded as breaks in therapy.…”

Systematic review of scope and quality of electronic patient record data in primary care

“…One study used video recording of the consultation to evaluate the EPR content compared with the use of notes and UK national statistics (fourth national study of morbidity in general practice, MSGP4) for comparative measures 18. Seven studies carried out questionnaire and telephone surveying for a reference standard with data gathered from the patient, carer, or both 13 14 19 20 22 – 24. These studies involved the sampling of a study population from the database for subsequent validation through questionnaires.…”

A review of studies of adherence with antihypertensive drugs using prescription databases

“…A Japanese questionnaire-based study found 49% of patients with well controlled blood pressure reporting adverse effects with their antihypertensive medicines and a statistically significant relationship between the number of reported adverse effects and nonadherence (Toyoshima et al 1997). However, it has been observed elsewhere that patients who discontinue are less likely to respond to questionnaires (Suarez et al 2000), so that the results of this study should be interpreted with caution. Certainly it is known that polypharmacy increases the risk of adverse effects due to drug interactions.…”

“…The length of this period ranged from 3 to 12 months; however, there was usually no attempt to justify this choice. A study based on the UK General Practice Research Database (UKGPRD) concluded that a 4-month period without prescriptions was not sufficiently long to identify new users of antihypertensive drugs and that a 12-month period would be more appropriate (Suarez et al 2000). This finding is not necessarily applicable to other databases, but it is possible that the studies choosing relatively short run-in periods may include a substantial number of patients who are not new to antihypertensive therapy.…”

“…There were no attempts to validate the choice of duration of the period without therapy. Suarez et al (2000), in their study of the UKGPRD, found that 4 months was an insufficient period for identification of new users of antihypertensive therapies; that is, they found that there were a large number of patients who, although failing to collect their prescriptions for 4 months, returned to some form of antihypertensive therapy. If this finding holds true for other populations, it appears that many discontinuations may be more properly regarded as breaks in therapy.…”

Systematic review of scope and quality of electronic patient record data in primary care

“…One study used video recording of the consultation to evaluate the EPR content compared with the use of notes and UK national statistics (fourth national study of morbidity in general practice, MSGP4) for comparative measures 18. Seven studies carried out questionnaire and telephone surveying for a reference standard with data gathered from the patient, carer, or both 13 14 19 20 22 – 24. These studies involved the sampling of a study population from the database for subsequent validation through questionnaires.…”