Showing posts with label quality of life. Show all posts
Showing posts with label quality of life. Show all posts

Wednesday, November 5, 2008

Adapting "quality of life" measures to a local audience

Evaluating the reliability, validity and minimally important difference of the Taiwanese version of the diabetes quality of life (DQOL) measurement
Original source: Health and Quality of Life Outcomes 2008, 6:87
Authors: I-Chan Huang (corresponding author), Jung-Hua Liu, Albert W Wu, Ming-Yen Wu, Walter Leite, Chyng-Chuang Hwang
Publication date: 28 October 2008
DOI (digital document ID): 10.1186/1477-7525-6-87
Requires subscription? No
Publicly-available abstract: Yes

Synopsis:
The authors' goal was to develop ways to measure Health-Related Quality of Life (HRQoL) in the Chinese language, primarily for use in Taiwan. They translated a standard survey (called DQOL) to measure diabetes-related HRQoL, put it to a test, and tried to find out where it worked and where it needed tweaking.

There are a number of standards for measuring HRQoL in general, and diabetes-related quality-of-life in particular. One issue is that even among the diabetes-specific surveys, there are differences: some look at quality of life based on energy, mobility, ability to function, and social aspects along with the issues of testing and maintaining control; others look at the effect of medical treatment and satisfaction with that treatment, as well as concern about eventual development of complications. In order to be meaningful, the surveys have to pose questions that have meaning within the culture in which they are presented, and which put the patient at enough ease to answer truthfully. (For example, questions about sexual activity will not be answered in a society where that discussion is taboo.) One aspect of this is rewriting the survey in the local dialect.

A major issue with health-related quality of life surveys is determining what the patient means, and way he perceives the care he is receiving, and what changes to his responses mean over the course of time. There are several methods of statistically analyzing these responses and comparing them to an "impartial" standard -- physical measurements of the patient's health.

The clinical measurements used to validate the survey included HbA1c (a measurement of average long-term blood glucose levels), blood glucose levels two hours after meals ("two-hour postprandial"), fasting blood glucose levels, and the presence of some of the most common complications of diabetes (neuropathy - loss of sensation; foot ulcers, infections, and amputations; cardiovascular issues such as heart disease; and cerebrovascular (brain circulation) issues such as stroke).

In addition, two other diabetes-related quality of life surveys were translated and made more appropriate to Taiwanese culture, and used to verify the results of the Taiwan-adapted DQOL and to make those results meaningful to researchers and public health professionals.

The authors discuss their methods of translating and localizing the DQOL, their analysis of the data, and the limitations of their research.

Reliability:
The authors are all professionals in either public health or medicine, and interested in how patients perceive their quality of life.
The sample used was relatively small, but of a reasonable size to test the effectiveness of the surveys being developed; however, all of the respondents were from the same health center in Taiwan, and only four had Type 1 diabetes. The authors also noted that this analysis was done over a cross-section of patients at one time, and one of the real strengths of measuring quality of life is how it is perceived to change over time.

Practical Applications:
This is a first step in being able to understand, from the Taiwanese patient's viewpoint, the effects of diabetes on his quality of life. Applying this information to medical practice will help improve the level of care, and the effect of care, provided to these patients.

This synopsis was based on the entire article.

Tuesday, November 4, 2008

Effects of adding a second drug to Metformin

Outcomes of adding second hypoglycemic drug after metformin monotherapy failure among type 2 diabetes in Hungary
Original source: Health and Quality of Life Outcomes 2008, 6:88
Authors: Gyorgy Jermendy, Diana Erdesz, Laszlo Nagy, Don Yin, Hemant Phatak, Sudeep Karve, Samuel Engel and Rajesh Balkrishnan (corresponding author)
Publication date: 31 October 2008
DOI (digital document ID): 10.1186/1477-7525-6-88
Requires subscription? No
Publicly-available abstract: Yes

Synopsis:
The authors' goal is to determine how well patients' blood glucose levels are controlled, and how the patients felt about their quality of life with diabetes, when metformin was not sufficient to control their diabetes and a second drug was added. The medical records of patients who had been on two oral diabetes drugs for at least a year were followed back for at least one year when they were on the two drugs, and going back as far as six months before the second drug was added. Other medical conditions that might affect the choice of medications, or that might need different medications, were tagged.

The goal of diabetes care was to achieve an HbA1c of under 6.5%. HbA1c is a long-term measure of average blood glucose levels; it is believed that sustained high blood glucose levels are the cause of many of the complications of diabetes. One issue that complicates this goal is that the HbA1c level includes the effects of unusually or dangerously low blood glucose -- hypoglycemia.

414 patients, average age 60 years, participated in this survey, in which they were asked about hypoglycemic incidents, satisfaction with their treatment, and overall health-related quality of life (HRQoL).

Hypoglycemic episodes were ranked as mild (little disruption to activities), moderate (requiring the to interruption of normal activities), or severe (requiring immediate medical assistance). The patients were also asked to report any swelling, weight gain, and digestive discomfort that might have occurred since starting the second drug. They were also given a standardized questionnaire to determine whether or not they took one, or both, drugs as prescribed.

27 percent reported hypoglycemic incidents, one third of that group reporting at least one moderate or severe hypoglycemic incident. Three-quarters of the patients did not meet their HbA1c goal after a year of therapy; many blamed their weight for this, though the surveys suggest it is more likely that this failure was because they were not taking their medications correctly. Reasons for not taking medications included side effects and the belief that the medications would cause them to gain weight. Patients who did not get their HbA1c below 6.5% were as a whole heavier than those who reached the goal, and they were less likely to be satisfied with the change in treatment. The participants felt that hypoglycemic incidents reduced their health-related quality of life; also, the longer they had diabetes, the lower their self-reported HRQoL.

Reliability:
The group of patients examined was relatively small, and because the individuals reported their issues themselves, it is possible that some did not admit to not using their drugs correctly, or to other issues that might affect the results of their care.

The results were published in a peer-reviewed journal, and the effectiveness of oral diabetes drugs is a hot issue. This study shows some possible reasons for why dual-drug therapy is not always successful.

It is important to note that all but one of the authors works for Merck, either as a direct employee or a paid consultant. Merck is the manufacturer of sitagliptin (Januvia), which is in a different class of oral diabetes drug from those used in the study (DP-4 inhibitors). The failure rates of both sulfonylurea and thiazolidinedione drugs used in the study could be used to build a case for the preferential use of Merck drugs Januvia and Janumet (Januvia plus Metformin) for diabetes management, which would be very profitable for Merck. Merck paid for the study.

Practical Applications:
The care protocols recently issued by both the American Diabetes Association and the European Association for the Study of Diabetes suggest either adding a sulfonylurea (a class of drug which helps the pancreas make more insulin) or moving directly to insulin injections if metformin by itself does not provide effective results. While some second-tier drugs such as Actos and Byetta were mentioned, the use of these and other classes of oral diabetes drugs (including DP-4 inhibitors such as Januvia) were considered more expensive and not as well-tested.

Another issue to consider is that the time-frames for changing ineffective therapy are much shorter in the current recommendations than those followed by the doctors in this study. Since diabetes is a progressive disease, it is possible that by the time the second medication was added, the disease had progressed too far for that medication to be effective.

For further reading:
New Major Changes in Recommendations for the Treatment of Type 2 Diabetes by ADA and EASD -- a synopsis of the new treatment recommendations from Diabetes In Control
Medical management of hyperglycaemia in type 2 diabetes mellitus: a consensus algorithm for the initiation and adjustment of therapy -- the abstract of the new treatment protocols, as published in Diabetologia

This synopsis was based on the entire article.