The Asymptomatic Hernia: Title and subTitle Break“If It's Not Broken, Don't Fix It”

Inguinal hernia is a common clinical entity, with more than 600 000 herniorrhaphy procedures performed yearly in the United States.¹ While hernias are often identified when patients notice groin discomfort, many hernias are discovered by clinicians in patients who have no or few symptoms.² The natural history of inguinal hernia is not well understood, because most hernias remain undetected and many detected hernias are surgically repaired. An unknown proportion of patients without hernia-related complaints will develop symptoms over time. While all patients with hernias have a risk of developing hernia-related complications such as incarceration or bowel compromise, there has been little evidence to quantify these risks.

When considering whether to have surgical repair for inguinal hernia, the risks and benefits of the procedure must be balanced against the risks and benefits of living with the hernia. For patients with hernia-related symptoms, this balance is most often influenced by the extent of their symptoms and the anticipated benefit of relief of these symptoms with surgical repair. For patients without symptoms, the benefits may include the avoidance of the risk of hernia-related complications in the future. The surgical community has long been divided about the appropriate approach to these asymptomatic or minimally symptomatic patients, both because of the uncertain risk of developing serious hernia-related complications and because of increasing appreciation of the risks associated with hernia repair, such as chronic pain and recurrence.

In this issue of JAMA, Fitzgibbons and colleagues³ report the long-awaited results of the first randomized trial of watchful waiting or surgical repair for patients with asymptomatic or minimally symptomatic hernias. More than 700 men were randomly assigned to a strategy of watchful waiting or Lichtenstein open tension-free hernia repair and were followed up over time. The investigators sought to determine the safety of a watchful-waiting strategy with regard to hernia-related complications (such as incarceration or bowel compromise) and the acceptability of watchful waiting with regard to pain and activity. The primary end points in the study (pain sufficient to limit activity, change in physical health component score of the Short Form-36 Version 2) were evaluated at 2 years and were similar in both groups. The risk of hernia incarceration was low—1.8 per thousand patient years, or 0.03% of study participants. Both groups had high levels of satisfaction with the care they received. This low risk of watchful waiting confirms prior estimates that were based on recall of patients who underwent hernia repair⁴ and is the best estimate to date of this risk.

Since much of the dynamic involved in counseling patients with asymptomatic hernias relates to the risk of hernia incarceration and bowel compromise, these findings should affect millions of patients with this condition. The other issue that drives decision making for patients is the likelihood that symptoms will develop over time and that once the hernia enlarges or becomes symptomatic, treatment may be more problematic in terms of both timing and outcomes. Here the study by Fitzgibbons et al is also informative in finding no differences in objective outcomes such as infection, length of surgery, or recurrence in those patients assigned to watchful waiting who ultimately did have surgery. This study reinforces the notion that watchful waiting is a safe and acceptable approach in men and can avoid the occasional but important adverse outcomes associated with surgical repair. In fact, the risk of postsurgical complication in patients undergoing surgical repair was much higher than the risks of a hernia-related complication in patients who were watched.

Some may find this study difficult to interpret because nearly 1 in 4 patients assigned to watchful waiting crossed over to receive surgical repair within 2 years, and nearly a third had undergone repair by the time the study closed at 4 years. Watchful-waiting patients who crossed over to receive surgical repair most often reported that increased pain was the reason they wanted repair, but only half reported that the pain limited usual activity at the time of crossover. Compounding this issue of crossover was that 17% of those assigned to the surgical repair group of the trial did not have surgery.

The study's analytic approach was intention-to-treat (ITT), in that patient outcomes were compared based not on the treatment they received but rather the treatment strategy they were intended to receive. It may seem difficult to make sense of a trial that purports to evaluate the outcomes of 2 approaches when nearly 40% of patients did not receive the treatment to which they were assigned. Some might be tempted to perform an “as-treated” analysis rather than the ITT analysis to really assess the effect of 2 different treatments. However, as-treated evaluations are often deeply flawed, because these comparisons are between groups that have not been formed by random assignment and that may well be heavily influenced by selection bias. Conversely, randomization to different treatment strategies balances the groups with regard to both known and unknown factors that may otherwise influence outcome.

The most important reason ITT analysis is essential is that it really provides the information that clinicians and patients need most when at a decision point. The key here is that this study was not comparing 2 treatments, but rather 2 treatment strategies. A study of treatment strategies is really what matters to clinicians and patients who are making decisions about how to manage this condition. It is impossible to determine at that decision point whether the nature of the patient's condition will change in the future (ie, become more symptomatic), and for that reason the ITT analysis answers the question about what happens to a group of patients who embark on a treatment strategy (even if they ultimately may not follow that treatment strategy). In counseling patients with hernias, physicians can say for at least this population of patients (older, male veterans in Veterans Administration medical centers) that beginning a strategy of watchful waiting was associated with a very low risk of complications and that outcomes at 2 years were no worse (and no better) than for those assigned to a strategy of prophylactic hernia repair. Moreover, there is a good chance that patients who start the watchful-waiting strategy will want the hernia repaired over time.

So what benefits will a strategy of watchful waiting achieve for the patient? Patients in the watchful-waiting group at least avoid the risks of surgical repair. One risk of tension-free surgical repair is that hernias will recur in 1% to 3% of patients and may then be more difficult to treat and carry a higher risk for a subsequent recurrence. Other risks include early complications (ie, cutaneous nerve injury, bleeding, and surgical site infection), each of which occur in approximately 1% of cases.^{5 - 6} More important but less frequent complications, such as ischemic orchitis and mesh-related infections, may occur, sometimes necessitating orchiectomy for the former and mesh removal for the latter.⁷ Lastly, surgeons are increasingly appreciating that chronic pain after hernia repair may affect 5% to 20% of patients⁸ and occasionally requires chemical or operative neurectomy.⁹

One of the most important responsibilities for physicians and other health care professionals is counseling patients about the risks and benefits of different treatment options. For surgical procedures this is even more challenging, because the benefits of the intervention are assumed while the risks of not doing the intervention are often difficult to quantify. To date, surgeons have had limited evidence with which to help the millions of patients with inguinal hernia make informed decisions about elective hernia repair. The study by Fitzgibbons et al³ provides important evidence that a strategy of watchful waiting is safe and that even though patients may eventually undergo hernia repair, when they do the operative risks and complications are no greater than the risk of prophylactic hernia repair.

It remains to be seen if these results apply to all populations with inguinal hernias. For instance, younger patients, women, and those with other types of hernia may have different risks of hernia complications, as well as perspectives on these strategies that might result in a different outcome. The environment a patient lives in or travels to frequently should also be considered in decision making regarding future risk. For example, access to appropriate levels of health care is a key component of a watchful-waiting strategy so that if the hernia becomes incarcerated, prompt treatment is available. This would not be an issue in health care systems in which emergency centers, on-call physicians, and universal health care coverage are all available, but this watchful-waiting strategy may not be appropriate in regions or countries where access to care is limited.

The edict primum non nocere has deep roots in medicine. For years, surgeons have been struggling to find the best way to avoid the greatest harm in patients with incidentally identified hernias. Now, physicians can counsel these patients with regard to both operative and nonoperative strategies, with a better sense of which will do the least harm. If the results of this study are reproduced in other populations and for other types of hernia, then the era of preventive hernia repair should go the way of prophylactic tonsillectomy, cholecystectomy, and appendectomy. Avoiding harm in this case is easy—it can best be accomplished by counseling and educating patients and only repairing hernias that cause symptoms.