Reply to Comment on “Gabapentin Versus Chlordiazepoxide for Outpatient Alcohol Detoxification Treatment”

TO THE EDITOR: We appreciate the comments made by Drs Kaur and Medhi on our study results and are grateful for this opportunity to respond. We would like to further analyze their observations and clarify the implications they have on our findings. They mention the range of scores possible on the Penn Alcohol Craving Scale (PACS) and point out a possible error in the means and ranges reported in our study. They correctly note that PACS is a 5-item self-administered scale with 7 possible responses to each question labeled 0 to 6 (total score range 30 points). Seven narrative descriptions follow each of the 5 items. For example, item 4 “How difficult would it have been to resist taking a drink during this period of time if you had known a bottle were in your house? ” is followed by responses ranging from “Not difficult at all = 0” to “Would not be able to resist = 6. ” The PACS form our subjects received had responses that were labeled 1 to 7 rather than 0 to 6. Thus scores could range from 5 to 35 (total score range 30 points). Changing the numerical anchors does not alter our overall findings, and we do not believe using 1 to 7 biased subjects to rate their craving more strongly than if the anchors were labeled 0 to 6. Although the difference in PACS scores at the end of the treatment period in our subjects did not reach statistical significance, the trend of less craving in the gabapentintreated group is consistent with findings of Myrick et al who found that alcohol withdrawal subjects treated with gabapentin experienced less craving than benzodiazepinetreated subjects. Drs Kaur and Medhi also correctly state that the cutoff score for “normal sleepers” on the Epworth Sleepiness Scale (ESS) is 10. Johns developed the ESS as a self-rated scale that asks “How likely are you to doze off or fall asleep in the following situations, in contrast to feeling just tired? ” for 8 different situations such as sitting and watching TV or being in a car idling at a stop light. Responses ranging from 0 = “would never doze” to 3 = “high chance of dozing” describe subjects’ self-rated propensity to fall asleep. A score <10 does not mean a subject feels no propensity to fall asleep, rather, it separates patients with diagnosed sleep disorders, including narcolepsy and obstructive sleep apnea syndrome (most having scores >10) from those without diagnosed sleep disorders (most having scores <11). Notably, Johns has analyzed ESS performance in subjects without sleep disorders. He concluded that, in normal subjects, ESS scores can vary from a very low to very high propensity to fall asleep across time and situations. We found that subjects receiving chlordiazepoxide had significantly higher mean ESS scores (higher propensity to fall asleep) at the end of treatment than subjects treated with gabapentin. This finding is also consistent with findings of Malcolm et al reporting higher ESS scores in lorazepamtreated subjects compared with those receiving gabapentin for alcohol withdrawal. (These are the same subjects described by Myrick et al.) We thank Drs Kaur and Medhi for pointing out that we neither fully described the instruments we used nor explained their statistical and clinical implications. We appreciate that they have drawn attention to this limitation in our article. It is important for readers to know what instruments are used in studies they are reading in order to properly interpret them and determine the place new evidence has in their own clinical decision making.