title: Proton magnetic resonance spectroscopy of brain to study the cerebral metabolic abnormalities in COPD patients: a case control study in north India.
abstract: BACKGROUND
  To investigate changes in the cerebral metabolism of nondiabetic and normolipidaemic patients with chronic obstructive pulmonary disease (COPD) using localised in vivo proton magnetic resonance spectroscopy (1H MRS), and to correlate these with the severity of disease.
  
  
  METHODS
  Twenty-eight symptomatic COPD patients and 19 healthy controls underwent 1H MRS of brain, pulmonary function testing and respiratory muscle strength evaluation. The parieto-temporal and occipital regions were localised for 1H MRS. The metabolic ratios of N-acetyl aspartate to cretinine (NAA/Cr) and choline containing compound to creatinine (Cho/Cr) were calculated by integrating area under the each peak.
  
  
  RESULTS
  The mean value of NAA/Cr and Cho/Cr in parieto-temporal area in COPD patients were (1.86 +/- 0.54) and (0.77 +/- 0.23), respectively. The mean values of NAA/Cr and Cho/Cr in occipital area in COPD patients were (1.75 +/- 0.44) and (0.61 +/- 0.25), respectively. Compared with healthy control subjects, the mean values of Cho/Cr in COPD patients were lower, both in parieto-temporal (0.77 +/- 0.23 vs. 0.89 +/- 0.35; p = 0.17) and occipital (0.61 +/- 0.25 +/- vs. 0.67 +/- 0.08; p = 0.36) areas of the brain.
  
  
  CONCLUSIONS
  The cerebral metabolism, pulmonary function testing and respiratory muscle strength altered in symptomatic COPD patients. The clinical significance of cerebral metabolic changes in COPD patients needs to be further investigated.
authors.affiliation: Department of Medicine, All India Institute of Medical Sciences, New Delhi, India. drsanjeevsinha2002@yahoo.com
authors.forename: Sanjeev
authors.initials: S
authors.lastname: Sinha
authors.forename: Virendra
authors.initials: V
authors.lastname: Kumar
authors.forename: N R
authors.initials: NR
authors.lastname: Jagannathan
authors.forename: Ravindra Mohan
authors.initials: RM
authors.lastname: Pandey