Does a vape a day keep the cigarettes away?
When the infamous adverts suggesting that e-cigarettes are “95% less harmful than cigarettes” appeared in 2015, it seemed to knock the stuffing out of smoking cessation services: why should soon to be bankrupt councils pay GPs and pharmacists to help people stop smoking when they could just buy a vape instead? Since then vapes have become a permanent presence in corner shops and school classrooms. But, despite their success as consumer products, vapes are still not licensed as smoking cessation aids. A clinical trial in China randomised people motivated to quit smoking to receive electronic cigarettes, varenicline, or nicotine chewing gum for 12 weeks with minimal behavioural support. E-cigarettes came out as non-inferior to varenicline—around 15% remaining abstinent from smoking after six months in these groups, compared with only 8.8% in the gum chewers.
JAMA Intern Med doi:10.1001/jamainternmed.2023.7846
SGLT2 inhibitor study leaves no stone unturned
Small studies of healthy volunteers given SGLT2 inhibitors have found that the drugs can increase the excretion of citrate—like a kind of lemon squeezer for the kidneys. This could, in theory, help to reduce the risk of renal stones through citrate’s reported anti-inflammatory effects, or by forming complexes that help to mop up some calcium. A new cohort study followed 716 406 people in the US with type 2 diabetes who were prescribed an SGLT2 inhibitor or a GLP-1 receptor antagonist. After a median follow-up of 192 days, rates of kidney stones were lower in those who were prescribed an SGLT2 inhibitor than those prescribed a GLP-1 receptor antagonist (14.9 v 21.3 events per 1000 person-years; hazard ratio 0.69 (95% CI 0.67 to 0.72)).
JAMA Intern Med doi:10.1001/jamainternmed.2023.7660
Another kick in the loin for eGFR
Calculating estimated glomerular filtration rate (eGFR) using a combination of creatinine and cystatin c levels (eGFRcr-cys in biochemistry lingo) is far more accurate than using creatinine-only based calculations eGFRcr (you add “eatinine” to the cr, not “ap”). As covered last year on this page, eGFRcr can be way off the mark compared with gold standard methods of assessing GFR. It gets dealt another blow by a new population based cohort study comparing the accuracy of eGFRcr and eGFRcr-cys at predicting outcomes. Stronger associations were seen with eGFRcr-cys across the board, including for mortality and progression to renal replacement therapy. For instance, higher rates of all-cause mortality were found when comparing an eGFR of 60 versus 80 mL/min/1.73 m2 when using eGFRcr-cys (hazard ratio 1.2 (95% CI 1.1 to 1.3)) but not for eGFRcr (HR 1.0 (0.9 to 1.0)).
Ann Intern Med doi:10.7326/M23-1138
A spoonful of empathy to help the complaints go down
Empathic statements delivered as a consultation trick rather than from a genuine interest and connection with your situation make me cross. It’s odd then, to see a systematic review of randomised studies of empathy interventions, which makes empathy sound like something that can be boxed up and delivered to patients. It concludes that “development, testing, and reporting of high-quality studies within well-defined contexts is needed to optimize empathy interventions that increase patient satisfaction.” One issue they found from the 14 randomised trials was heterogeneity in how empathy was delivered—long may that continue.
Ann Intern Med doi:10.7326/M23-2168
Iodine or chlorhexidine for preoperative antisepsis?
In 1867 Joseph Lister published a series of articles in the Lancet describing his success in reducing rates of infection by using carbolic acid as an antiseptic. In one case an open fracture wound was dressed daily with pieces of lint dipped in carbolic acid. In another Lister described his surgical methods after a 10 year old boy crushed his arm in the machinery while working in a factory: “I sawed off the protruding portion of the ulna, and the tags of muscle having been previously clipped away, I applied carbolic acid freely to the whole interior wound…”
A recent cluster randomised crossover trial in the New England Journal of Medicine has a lot in common with Lister’s work—even if the writing is a little more sanitised and the results less dramatic. The study compared iodine with chlorhexidine for preoperative antisepsis in people with closed and open fractures. A small benefit from using iodine was seen in those with closed fractures, amounting to one infection prevented per 100 operations. For open fractures, the authors found no significant difference in infection rates between the two antiseptics.
N Engl J Med doi:10.1056/NEJMoa2307679