You will be presented with the full text of a biomedical research paper. Please write an abstract for this paper. Your response should include the abstract and no additional text.

Paper text:
diabetic nephropathy became the leading cause of chronic dialysis in 1998 . since then , the incidence of this condition has increased , with only a recent plateau .
however , diabetic nephropathy continues to account for a large proportion of all cases of chronic kidney disease ( ckd ) , and remains by far the most common underlying cause of chronic dialysis among all kidney diseases5 , consequently leading to the escalation of healthcare costs , thus representing a compelling medico - social issue of interest .
the classification of diabetic nephropathy ( hereafter  classification ) developed earlier by the research group of diabetic nephropathy at the ministry of health , labor and welfare ( mhlw)6 , and later revised by the joint committee on diabetic nephropathy ( hereafter  committee)7 is widely used in japan . however , as the concept of ckd was proposed , followed by the classification of ckd stages8 , it became clear that there exists a subpopulation of patients with discrepant classifications of diabetic nephropathy and ckd .
this is thought to be because of the fact that diabetic nephropathy is primarily classified according to the extent of albuminuria in addition to the glomerular filtration rate ( gfr ; i.e. , creatinine clearance [ ccr ] ) , whereas ckd is primarily classified based on the estimated gfr ( estimated gfr [ egfr ] ) .
meanwhile , egfr has become increasingly used to assess gfr , and a new classification of ckd was developed in 20129 . against this background ,
the committee therefore discussed issues of interest in depth , and sought to develop a revision of the classification .
prior to revising the classification , as part of a mhlw - subsidized project on kidney disease , entitled  diabetic nephropathy research , from the ministry of health , labor and welfare of japan,
a  historical cohort study was conducted by the research group of diabetic nephropathy , mhlw , involving a total of 4,355 subjects with type  2 diabetes from 10 participating healthcare facilities with the aim of evaluating renal events ( i.e. , a decrease in egfr to half the baseline level and/or the need for dialysis ) , cardiovascular events and all - cause mortality10,11 . summarized below are the major findings of that study ( for detailed information , please access the mhlw website http://www.mhlw.go.jp/ or refer to the literature cited above ) . 


renal and cardiovascular events and all - cause mortality were significantly increased in the subjects with micro- or macroalbuminuria compared to that observed in the subjects with normoalbuminuria . 

 in those with renal impairment ( defined as a gfr < 60  ml / min/1.73 
m ) : 

 the risk of renal events increased in association with the onset of microalbuminuria and further increased with the onset of macroalbuminuria in the subjects ; 

 the risk of cardiovascular events was increased those with micro-/ macroalbuminuria ; and 

 all - cause mortality was increased in the subjects with macroalbuminuria as well as those with normoalbuminuria and microalbuminuria who exhibited a gfr of < 30  ml / min/1.73  m. 
 renal and cardiovascular events and all - cause mortality were significantly increased in the subjects with micro- or macroalbuminuria compared to that observed in the subjects with normoalbuminuria . 
 
 in those with renal impairment ( defined as a gfr < 60  ml / min/1.73  m )
: 

 the risk of renal events increased in association with the onset of microalbuminuria and further increased with the onset of macroalbuminuria in the subjects ; 

 the risk of cardiovascular events was increased those with micro-/ macroalbuminuria ; and 

 all - cause mortality was increased in the subjects with macroalbuminuria as well as those with normoalbuminuria and microalbuminuria who exhibited a gfr of < 30  ml / min/1.73  m. 
 the risk of renal events increased in association with the onset of microalbuminuria and further increased with the onset of macroalbuminuria in the subjects ; 
 
 the risk of cardiovascular events was increased those with micro-/ macroalbuminuria ; and 
 
 all - cause mortality was increased in the subjects with macroalbuminuria as well as those with normoalbuminuria and microalbuminuria who exhibited a gfr of < 30  ml / min/1.73  m. while that study was not a true prospective study , and involved only a limited number of facilities and patients from a population known to be less prone to cardiovascular events than those in western countries , the findings provide important insight into the prognosis of diabetic nephropathy in japanese patients .
therefore , in seeking to revise the classification , the committee gave due consideration to the above findings .
the bulk of evidence for the classification of diabetic nephropathy comes from randomized controlled studies enrolling patients with diabetic nephropathy as defined based on the extent of albuminuria , and very little evidence is available for diabetic nephropathy as defined based on gfr . 
 

the current  medical service fee schedule for guidance on preventing diabetes - associated dialysis was developed with the classification in mind . 
 

the  guidelines for clinical efficacy evaluation of pharmacological agents for diabetic nephropathy ( draft) currently in use were developed with the classification in mind . 
 
therefore , after giving due consideration to all of these issues during the course of several sessions , the committee decided to leave the classification essentially unchanged for now ( table1 ) , while showing how it might be aligned with the widespread ckd classification based on gfr ( egfr ; appendix   1 ) .
the former is not , however , presented as a heat map , due to the limitations of the study referred to above , which involved a small number of patients with diabetic nephropathy and included no dialysis patients , providing the basis for this revision .
again , as all kidney diseases affecting patients with diabetes are covered in the classification , the committee called for attention , with notes included where required , in order to highlight the importance of the differential diagnosis between diabetic nephropathy and non - diabetic kidney disease in all stages .
the differential diagnosis calls for collaboration with nephrologists ; such collaboration is not limited to cases requiring a renal biopsy .
furthermore , given that the disease may not always progress in some patients , numerous notes were included in the table in order to call attention to these cases .
additionally , in view of the potential need to use multiple antidiabetic drugs over time ,  key precautions in view of drug use are included below the table .
the major revisions to the classification are summarized as below : 
 egfr is now substituted for gfr in the classification . 
 

the stages used in the classification have been simplified to include normoalbuminuria , microalbuminuria , macroalbuminuria and kidney failure . 
 

the division between a and b ( early versus late macroalbuminuria ) in stage  3 has been abandoned , and a and b have been reintegrated , due to the paucity of evidence for proteinuria of 1  g / day as the threshold for dividing the stage . 
 

kidney failure has been redefined in all cases as a gfr less than 30  ml / min/1.73  m , which represents the threshold value for kidney failure obtained by quantifying the existing definition of kidney failure in the classification based on the classification of the japanese society of nephrology ( jsn)12 with all other pre - kidney failure conditions redefined as a gfr of 30  ml / min/1.73  m or greater . 
 

qualifying or illustrating phases in parentheses , such as  e.g. , incipient nephropathy , have been retained throughout the classification , as they have become common currency in the field , although their removal from the classification was suggested during the process of revision . 
 

stress is now placed on the differential diagnosis of diabetic nephropathy versus non - diabetic kidney disease as being crucial in all stages of diabetic nephropathy . 
 
classification of diabetic nephropathy 2014jdi diabetic nephropathy does not always progress from one stage to the next .
the revised classification takes into account findings on the prognosis of type 2 diabetic patients from a  historical cohort study carried out as part of the ministry of health , labor and welfare - subsidized project on kidney disease , entitled  diabetic nephropathy research , from the ministry of health , labor and welfare of japan'10,11 .
although a glomerular filtration rate ( gfr ) of less than 60  ml / min/1.73  m is consistent with the diagnosis of chronic kidney disease , underlying causes other than diabetic nephropathy might be involved in patients with a gfr below 60  ml / min/1.73  m , thus calling for the differential diagnosis between diabetic nephropathy and any other potential non - diabetic kidney diseases . 
patients with microalbuminuria are to be diagnosed as incipient nephropathy after the differential diagnosis based on the criteria for an early diagnosis of diabetic nephropathy .
precautions are required in patients with macroalbuminuria , in whom renal events ( e.g. , a decrease in estimated gfr [ egfr ] to half its baseline value , the need for dialysis ) have been shown to increase as the gfr decreases below 60  ml / min/1.73  m. all patients with a gfr of less than 30  ml / min/1.73  m are classified as showing kidney failure , regardless of their urinary albumin / protein values . however , in those with normoalbuminuria and microalbuminuria , the differential diagnosis is required between diabetic nephropathy and any other potential non - diabetic renal diseases .
key precautions in view of drug use : this table is intended , first and foremost , as a classification of diabetic nephropathy and not as a guide to drug use .
all drugs , including antidiabetic drugs , particularly renally metabolized agents , are to be used in accordance with their prescribing information , with due consideration to relevant factors , such as gfr , in each patient . of note , the american diabetes association ( ada ) proposed in its clinical practice recommendations 2013 that all cases of albuminuria of 30  g / mg cr ( = mg / g cr ) be defined as 
increased urinary albumin excretion, thus abandoning the division between micro- and macroalbuminuria13 . again , while this concept was retained in the clinical practice recommendations 2014 , the ada further proposed that microalbuminuria and macroalbuminuria be redefined as persistent albuminuria of 30299  mg/24  h and 300  mg/24  h , respectively14 . while this change may result in the terms micro- and macroalbuminuria ceasing to be common currency in the clinical setting in the usa , to avoid confusion ,
the committee has chosen not to follow suit and rather err on the side of caution , thereby retaining these terms in the classification , given that they are less likely to no longer be used in scientific publications and are expected to remain common currency in japan .
last but not least , with a number of multicenter prospective studies currently underway , including the japan diabetes complication and prevention prospective ( jdcp ) study , jsn registries , japan diabetes clinical data management ( jddm ) studies and japan diabetes optimal integrated treatment for three major risk factors of cardiovascular diseases ( j - doit3 ) randomized study , the committee also plans to further revise the classification in a timely fashion as required , as relevant evidence becomes available from these and other studies .
in order to resolve the discrepancy between the existing classification of diabetic nephropathy and the current classification of ckd stages , the joint committee on diabetic nephropathy revised its classification of diabetic nephropathy . the new classification has already been uploaded onto the website of each member society represented on the joint committee as of january 10 , 2014 . again , in view of further revisions in the years to come , the joint committee has termed the revised classification , as the  classification of diabetic nephropathy 2014.
the joint committee on diabetic nephropathy has revised its classification of diabetic nephropathy ( classification of diabetic nephropathy 2014 ) in line with the widespread use of key concepts , such as the estimated glomerular filtration rate ( egfr ) and chronic kidney disease ( ckd ) . in revising the classification , 
 the committee carefully evaluated , as relevant to current revision , the report of a study conducted by the research group of diabetic nephropathy , ministry of health , labor and welfare of japan . 
 major revisions to the classification are summarized as follows : ( i ) egfr is substituted for gfr in the classification ; ( ii ) the subdivisions a and b in stage  3 ( overt nephropathy ) have been reintegrated ; ( iii ) stage  4 ( kidney failure ) has been redefined as a gfr < 30  ml / min/1.73  m2 , regardless of the extent of albuminuria ; and ( iv ) stress has been placed on the differential diagnosis of diabetic nephropathy versus non - diabetic kidney disease as being crucial in all stages of diabetic nephropathy .