Two Cases of Progressive Chronic Kidney Disease with Solid Improvement After the Cessation of Smoking

BACKGROUND: The close relationship between smoking and the progression of chronic kidney disease has been shown by many studies. We herein report two cases where it appeared that the cessation of smoking led to the inhibition of the progression of chronic kidney disease.
CASE REPORT: Case 1 was a 35-year-old woman with IgA glomerulonephritis. We prescribed dilazep hydrochloride hydrate (300 mg daily) to treat IgA glomerulonephritis and lansoprazole (15 mg daily) for reflux esophagitis. She had a history of smoking 20 cigarettes/day ×15 years, but finally quit smoking two years prior to this report. The decline in her estimated glomerular filtration rate (eGFR) showed a clear improvement (–0.13 mL/min/1.73 m²/year) compared to the eGFR observed while she was smoking (–1.75 mL/min/1.73 m²/year).
Case 2 was a 69-year-old man with a history of elevated blood sugar since his 40s. He had a history of smoking 30 cigarettes/day ×40 years, but quit smoking, in a splendid fashion, five days after his first visit to our hospital four years prior to this report. The eGFR decline in the 4 years after smoking cessation (–2.48 mL/min/1.73 m²/year) showed a clear improvement in comparison to the eGFR observed while he was smoking (–5.37 mL/min/1.73 m²/year).
CONCLUSIONS: We herein report two cases of progressive chronic kidney disease with solid improvement after the cessation of smoking. We speculate that these two cases did not necessarily show a direct suppressive effect of chronic kidney disease progression by smoking cessation, rather that smoking cessation included the elimination of various smoking-associated risk factors for chronic kidney disease, resulting in inhibition of disease progression.

Keywords: Renal Insufficiency, Chronic, Smoking, Smoking Cessation