How reliable are “reputable sources” for medical information on the Internet? The case of hormonal therapy to treat prostate cancer

Abstract

Objectives

Prostate cancer patients, as well as their caregivers and healthcare providers, often search the Internet for information about treatment options. We aimed to assess how accurate and up-to-date information about prostate cancer treatments is on websites owned and managed by health-related organizations that most patients and health care providers would consider to be the most trustworthy, based on the reputations of the site providers.

Materials and methods

We reviewed 43 noncommercial and easily found websites that offered extensive information on treatment options for prostate cancer patients. To assess how comprehensive the sites were, we focused on the information they provided on alternative hormonal therapies to commonly prescribed luteinizing hormone-releasing hormone (LHRH) agonists, namely GnRH antagonists and parenteral estradiol.

Results

Only 14 of 43 websites presented GnRH antagonists as a therapy option for prostate cancer. Sixteen of these 43 websites presented estrogen as a possible treatment option, but only 1 of the 43 websites contained current information on parenteral estrogen treatments. Less than half of the sites provided time stamps indicating when they were last updated. Furthermore, most sites with time stamps were not in fact up-to-date based on the information posted on the site.

Conclusions

Few seemingly reputable Internet sources for medical information provide viewers with the detailed and up-to-date information that they may expect from such sites when searching for alternatives to standard treatment for androgen suppression. Strategies for keeping such websites up-to-date and reliable are discussed. Sites may improve their credibility and usefulness if they (1) present all evidence-based treatment options, (2) regularly update and time stamp their information, (3) acknowledge that their recommendations on treatments may become out-of-date quickly, (4) and direct viewers to information on relevant, active clinical trials. Maintaining high quality sites may ultimately depend on users taking the initiative to inform website owners when their sites are out-of-date.

Introduction

Individuals commonly seek information on medical conditions that have recently been diagnosed with, ongoing health problems, and/or medications that have been prescribed or recommended [1], [2], [3], [4]. Concerns in these areas draw patients, family, and healthcare providers alike to the Internet, despite the fact that health-related information on the Internet is acknowledged to be variable and often unreliable [5], [6], [7], [8], [9], [10], [11], [12], [13]. As of last year, the Internet has overtaken healthcare providers as the primary source of health information for cancer survivors [14].

Because there is lack of consensus about the best treatments for prostate cancer, prostate cancer patients and those concerned about their care, are particularly drawn to the Internet for information on treatment options [15]. Dolce [14] has documented how disenchantment with the information and options presented to cancer patients by their physicians often drives patients to the Internet in search of newer, better, or alternative treatments.

Currently, a Google search on the 3 words “prostate,” “cancer,” and “treatment” returns over 21 million hits (with 1.39 million in Google scholar alone). Given the sheer volume of sites and the high variability of information on the Internet, those searching for reliable medical information are likely to consider some sites more trustworthy than others. Sillence et al. [16] showed that Internet users more readily trust sites that (1) are better designed (e.g., good layout, less pop-ups); (2) seem to present unbiased information; (3) appear to consider patient perspective; and (4) are owned by reputable organizations. Nonprofit organizations engendered the most trust in this regard and in several studies have been shown to have the most reliable information [17], [18].

In this study, we examine the quality of medical information on Internet sites that both patients and healthcare providers might expect to be highly reliable and up-to-date based on the mission and prestige of the organizations that own the sites. For this analysis, we use a specific common medical treatment for advanced prostate cancer, namely hormonal therapy, as our “test case” to explore the quality of information available to patients and healthcare providers on those sites. All the sites had unquestionably good, professional web page design so their visual appeal was not a concern. In contrast to most previous studies on the quality, reliability, and readability of Internet information (as cited above), we focused on the issue of whether these websites were as comprehensive, reliable, and up-to-date as physicians themselves would expect them to be.

Approximately half of men treated for prostate cancer will be offered “hormonal therapy” at some point during their treatment [19]. This therapy can be delivered via either surgical castration, or various drugs that suppress testosterone production or the ability of androgens to bind to prostate cells. Recent research shows that patients are poorly informed about what hormonal therapy means and the side effects of androgen deprivation [20], [21]. Because of the large side effect burden from the luteinizing hormone-releasing hormone (LHRH) agonists, patients on these drugs are a population that might be particularly drawn to the Internet in search of alterative treatments. Furthermore, in the disease trajectory, long-term androgen deprivation is offered to patients with rising PSA after local treatments have failed, or the disease is too advanced for local treatments to be appropriate. Patients are thus offered this treatment at a critical time when local (i.e., curative) therapies are no longer options. As such, starting androgen suppression for systemic disease carries with it the message that a cure is unlikely. This is a moment when a patient may feel the greatest disenchantment with the medical care presented to them and aggressively search out new options [14].

Our data are drawn from 43 reputable websites that contained information on options for hormonal treatment. By reputable sites we mean ones that belong to (1) national and international cancer organizations, (2) prostate cancer-specific nonprofit organizations, (3) medical societies, such as the American Urological Association and the Canadian Urological Association, (4) online health encyclopedias, (5) universities, and (6) well-established health information websites, such as WebMD. Our aim was to determine the level of detail, completeness, and accuracy of information provided on such presumably reputable websites, based on the information they provided on alternatives to standard androgen suppression treatments. We focused specifically on the information regarding gonadotropin-releasing hormone (GnRH) antagonists and estrogens. Both are alternatives to more established hormonal therapies used to suppress testosterone. GnRH antagonists are quite new and estrogen treatments are much older and antiquated, but being revived because of improvements in dosing and delivery [22], [23]. We discuss our findings as they pertain to patients' and healthcare providers' needs and expectations of medical information on the Internet.

By way of background, LHRH agonists are the most commonly prescribed drugs in North America, Europe, and other industrialized countries for androgen suppression. At any one time in North America, approximately 600,000 men are on these drugs [19]. There are alternative hormonal treatments with documented efficacy for the treatment of advanced prostate cancer, although they are less often prescribed. These include GnRH antagonists, the most widely available of which, degarelix, received Food and Drug Administration approval in the United States in 2008, and European approval by the European Medicines Agency in early 2009. Thus, we used Internet information on GnRH antagonists as one index of how current websites are in the information they post on alternative hormonal therapies to LHRH agonists.

The other hormonal treatment that we tracked was parenteral estradiol. Oral estrogens were the first established pharmaceutical treatment for prostate cancer but fell out of favor because they were associated with a high incidence of thromboembolic events. That risk was reduced with LHRH agonists, which replaced oral estrogen some three decades ago. However, the LHRH agonists are expensive drugs, costing the Medicare system in the United States over a billion dollars a year [24]. The LHRH agonists also have increasingly been shown to have their own detrimental side effects, including osteoporosis, hot flashes, fatigue, reduced libido, and increased risk of metabolic syndrome, all of which reduce patients' quality of life [25], [26], [27]. The severity of these side effects has prompted many patients to explore other options for androgen suppression or to go on LHRH agonist therapy intermittently [28], [29], [30].

Research over the last decade has shown that transdermal estradiol produces effective tumor response, while causing fewer cardiovascular problems than oral estrogens [31], [32], [33], [34], [35]. At the time we collected our data, phase II clinical trials were nearly complete and Phase III trials had been approved for funding, which compare the effectiveness of transdermal estrogen with LHRH agonists for tumor suppression and disease specific mortality. There is evidence that estrogens can help preserve libido in androgen-suppressed males [36], and transdermal estradiol is occasionally offered as supplemental therapy to patients on LHRH agonists who are particularly bothered by hot flashes.

There is renewed interest in using estrogens to treat prostate cancer [22], [23]. We included parenteral estradiol as one of our two test cases for the comprehensiveness of information about hormonal therapies for prostate cancer because of the long history of estrogens in prostate cancer treatment, and because of growing evidence of reduced thromboembolic risk with transdermal administration. The growing evidence of detrimental side effects of the LHRH agonists makes information on alternative hormone therapies reasonable indexes for how comprehensive and current “premiere” prostate cancer websites are in providing information on treatment options for prostate cancer patients in need of androgen suppression.